This time of year, the majority of fantasy columns are about the latest hot pickup for the week ahead. The Fantasy Lab likes to think on a grander scale, though, not just one day, week, month or even season at a time. So it should come as no surprise that the focus today is on keeper leagues and all of the wonderfully different kinds of keeper prospects that exist in fantasyland. But even if you're not in a keeper league, this should help you immensely for the final weeks of the season and for preparing for next year's draft.

Newbies often ask, "What makes a great keeper?" There are obviously many different elements that go into determining this, but there are two that stand out above the rest: your personality as a fantasy owner and your league's rules. The problem with this is that The Fantasy Lab knows neither. And since these can be so vastly different, potential keepers have been grouped together in similar tiers, so these two factors can come into play and interact with the tiers versus forcing you to figure out a straight list of my keeper rankings and how you and your league fit in.

Determining your personality as a fantasy owner means asking yourself questions to figure out how you play the game. What players do you love? Who do you want to build your team around? Do you like big men or floor generals? What's your risk level? Do you like to make trades? These questions and more can help you figure out who to keep or who to target in trades to keep in the future.

As for the other elements that go into determining a great keeper, the Fantasy Lab could write a whole book about it, but some of the factors that have been weighed in coming up with these tiers include: age, experience, opportunity, position, team/coach and his style, career arc, trends, injury history, contract terms, replacement players (backups), off-court behavior and much more. Now that you know some of what has gone into grouping these potential keepers and non-keepers, let's start identifying them.

PG Chris Paul, SG/SF Kevin Durant, SF LeBron James, SG Kobe Bryant, PF Dirk Nowitzki

A winning fantasy basketball team is built on a rock-solid foundation. Any one of these seven players can be your foundation. Each player is unique, bringing a different skill set to the table; it's really a matter of personal preference as to how you want to construct your roster. No matter which direction you are fortunate enough to head in if you have one of these cornerstones in tow, just know you are starting off the 2009-10 season on the right foot.

Part of the reason for the tier system is to group similar players together, but it's also so the Lab doesn't have to explain each player specific rank. However, for this top tier only, the players are listed in the Lab's preferred order, but you can make a case for rearranging any of the names to be your top keeper choice. Depending on your scoring system, either Paul or LeBron could be atop the rankings, and both are still under 25 years old. Durant is only 20 years old and is quickly becoming a force across eight categories. He could win the scoring title next year while quite possibly becoming fantasyland's top player. Not to hype him up or anything. The Lab did that already in early January -- decreeing him the best keeper 22 years old or younger -- just before his ascent into top-five territory. Kobe is Kobe. And while it's true Dirk is getting older, he has "old man" skills that age well, so a loss of athleticism won't affect his game much. He's solid for another three years, easy.

PG/SG Brandon Roy, PG Derrick Rose, PG/SG Dwyane Wade, F/C Amar'e Stoudemire, C Yao Ming, F/C Tim Duncan, PG Deron Williams, SG/SF Danny Granger, C Dwight Howard

Roy continues to improve in his third year and has no weaknesses in his game. It's really hard to knock him, but you have to keep in mind his injured heel and all the other young talent around him that could dip into his numbers ... Rose doesn't shoot three-pointers yet and his FT shooting has struggled, but he was thisclose to being included in the cream of the crop tier because of the expected improvement upon his vast talent and unreal athleticism at the PG spot. ... Wade still has turnover, three-point and FT percentage issues, but the real concern is the reckless abandon with which he plays. He's been injured too many times for my liking. Also, his pending divorce sounds pretty nasty and if it becomes a public spectacle, it could get ugly for Wade. Just something to keep in mind, but it's doubtful that any problems will manifest from this ... Stoudemire has had microfracture knee surgery and now serious eye surgery as well. Plus, his future in Phoenix is unsure. It shouldn't matter though; his talent will shine through no matter what situation he ends up in. ...

Yao is as solid as a California redwood, but he's been chopped down by season-ending leg injuries before. Time won't help his knees and feet when you're that tall and big ... Duncan has done the same thing for a decade plus and isn't slowing down at all. He's posting some of his best numbers in years, but he does have tendinitis in at least one knee and it's clear that his best days are behind him ... Deron Williams is a double-double guy in the John Stockton role in Jerry Sloan's offense. That means solid production for the next decade. If only he could be a better thief and hit more treys ... Granger was bound for the top tier, but this foot injury coupled with whispers about an old knee injury place him on this list, but that's the only reason and it's a flimsy one at best. Lastly, Howard. He's a centerpiece in every way imaginable. Too bad he'll sink you in FT percentage and turnovers, too. If you can live with that, there's a whole lot of Dwight to love.

F/C Pau Gasol, F/C Chris Bosh, SF/PF Kevin Garnett, PG/SG Joe Johnson, SG/SF Andre Iguodala, SG Kevin Martin, PG Tony Parker, PG Jose Calderon, SG/SF Hedo Turkoglu

Pau should be in the group above, but he's held back for a couple of reasons. The first is his penchant for getting injured. The second is the continued development of Andrew Bynum alongside him. But most important, it's the decrease in blocks. After reaching a career-high of 2.1 bpg just two years ago, Pau is down to just 0.9 rejections per night ... Bosh is the same way. He's all points, rebounds and FT shooting. The blocks have dried up, his knee is a bit balky and he could go from Alpha Dog to second fiddle as a free agent after next season ... Always a picture of health, KG has dealt with injuries each of the past two years. Plus, he's sharing the load in Boston ... JJ is still holding court in Atlanta, but will 2006-07 prove to be his career year? It's looking that way now ... Iguodala stepped his game up to another level this year, but that was only after Elton Brand's season ended and he stopped stifling Iguodala. What happens when he returns next year?

The team fell apart around him, but Kevin Martin is still scoring like a rock star. He doesn't bring much help in the peripheral categories, but the FT percentage, threes and points make him worth keeping ... The Spurs' Parker gives you points and some assists, but he doesn't shoot threes and never will, nor does he thieve, board or block shots ... Calderon has played just four years in the league, but he'll be 28 when next season starts. His percentages are high, but he needs to shoot more for them to have an impact ... Turkoglu is Orlando's go-to guy in the fourth, but he's thinking of opting out to test the free-agent waters. Going elsewhere could cut into his production, plus he won't have the same drive that helped land him his big contract.

PG Devin Harris, PG Rajon Rondo, PF David West, SF/PF/C David Lee, SF/PF/C Andrea Bargnani, PG Mo Williams, F/C Nenê, C Andris Biedrins

Any fantasy player lucky enough to own one or more of these eight players is probably doing pretty well in their league right about now. By most accounts, these players are classified as having their breakout years. That means they were selected way below what their production has returned. Hopefully this helps you in your keeper league's rules. Regardless, all eight players still have room to grow and could very well top this year's numbers. Each has demonstrated growth in their game throughout the year, making their breakthroughs just that, breakthroughs, not one-year wonders. The Lab recommends holding onto anyone from this tier.

F/C Troy Murphy, SG/SF Stephen Jackson, SF/PF Charlie Villanueva, PG/SG Nate Robinson, PG Chris Duhon, F/C Memo Okur, SF/PF/C Boris Diaw

The same can't be said for this tier. Each of these players has been a boon to fantasy teams this year, but the same can't be said for next year. The Fantasy Lab does not recommend keeping any of the players in this tier, and we'll tell you why.

Murphy is shooting a career-high in field-goal percentage and three-point percentage (leading to a career-high in 3PM). He's also averaging career-bests in rebounds, assists and steals. Career years eight seasons into the NBA are very rare, more so when it hasn't been a gradual build up to a culmination like this.

Captain Jack has been otherworldly this year, and very few could say that when he started his career five teams and nine years ago. But he is on the verge of completing back-to-back 20 ppg seasons. His minutes likely can't stay above 40 next year, though, and much of his success is tied to Don Nelson and his unusual coaching style. Having a player's value dependent on the coach is risky, especially with Nelson constantly flirting with retirement. Plus, Monta Ellis will be back in full force next year.

Speaking of coaches affecting a player's value, Mike D'Antoni and his "seven seconds or less" offense had turned scrubs into fantasy superstars, namely little men Nate Robinson and Chris Duhon. It's hard to recommend holding onto either given their histories before D'Antoni's arrival and the extended minutes D'Antoni was forced to play them this year. He'll have more depth next year as he continues to mold his team. Also, he hasn't been very consistent with playing time for Robinson.

Villanueva has been Milwaukee's saving grace with Andrew Bogut and Michael Redd out of action for extended periods of time. Still, it's hard to imagine Scott Skiles allowing him to touch the ball this much next year. Okur is shooting a career-high in all three percentages by a wide margin. He'll regress to his career averages, which weren't really keeper level to begin with, especially since he substitutes 3PM for blocks, not ideal for a center that you're building around.

Lastly, Diaw, we've seen this before -- a breakthrough season in your first year with a new team. It might stick since Larry Brown is fueling his fire and loves his astronomical basketball IQ, but we'd prefer to see it again before bringing him aboard the next few years' teams.

SF/PF Shawn Marion, SF/PF Josh Smith, SF Carmelo Anthony, SF/PF Gerald Wallace, SF Caron Butler

These five fantasy All-Stars all took a step back this season. That's surprising considering they are all in their prime or just entering it. In all likelihood, you will probably keep all of these guys again, but the picture isn't as rosy as it was entering the year. For starters, Marion demonstrated he was a product of D'Antoni's system and is proving to be a self-centered complainer concerned more about his contract than his team. That affects your future on-court performance ... Smith has regressed when it comes to his already terrible shooting and isn't blocking shots like he used to -- something that happens to "athletic" shot-blockers over the years as opposed to the "tall" shot blockers ... Wallace continues living up to his nickname of "Crash" and can't be trusted to stay healthy ... Butler's numbers have all decreased, even without Gilbert Arenas playing. Agent Zero will be playing next year, finally ... And Melo, wow, what happened to him? His field-goal shooting is down six percentage points, his scoring is down from 28.9 ppg two years ago to just 21.6 ppg. He's not nearly the player his name recognition says he is.

SF/PF Rashard Lewis, SF/PF Antawn Jamison, SG/SF Ray Allen, PG Steve Nash, SG/SF Vince Carter, PG Chauncey Billups, SG/SF Paul Pierce

Unlike Melo, these guys deliver on what their name promises. You know what you're going to get year after year from this bunch of 30-plus players. Yes, Rashard Lewis will be 30 by the time the season starts next year. We know it only seems like a few years ago that the high school senior was sobbing in the Green Room on draft day. Now, he's top option for 3PM and contributes in every category ... Jamison is known for his toughness and almost never misses time. He's a 20 and 9 guy with steals and threes for a little while longer ... Allen and Billups are playing at the same elite level as they have for years, no matter what team they are on ... While D'Antoni's departure cut into Nash's dimes and nearly earned him a spot in the tier above this one, his numbers are still elite and he keeps himself in phenomenal condition ... Did you know that Pierce is the reigning Finals MVP? He's assuming no one knows and is telling them with every single game he plays.

C Marcus Camby, PG Jason Kidd, F/C Carlos Boozer, PG Andre Miller, PG/SG Allen Iverson, PG Baron Davis, F/C Emeka Okafor, F/C Zach Randolph

These players are the guys who you don't want to keep, but you probably should for at least another year. In other words, be a realist, not an idealist. Whether it's old age, injury history, poor percentages, off-court trouble, prima donna status, overhyping, non-sexiness, general loathing or any other excuse in the book, these guys all have a reason not to be kept. But then you look at their numbers year after year and it seems foolish to keep other players over them. The Lab certainly wouldn't want any of these players as keepers, but if we absolutely had to ...

F/C LaMarcus Aldridge, PG/SG Monta Ellis, SG Ben Gordon, SF/PF Paul Millsap, PG Raymond Felton, F/C Al Horford, SF/PF Tyrus Thomas

This particular group of players is difficult to gauge. On one hand, they appear to be on the rise in their young NBA careers, but after having played three or four seasons now, they probably aren't going to get much better statistically, at least not without switching teams. All have their positives; all have their negatives. If you are willing to live with the production they gave you this year, then you won't be disappointed. If you are hoping for a giant leap forward, you will be saddened. Some incremental improvement can be expected, especially from the big men listed here as they refine their post play, but what you see now is pretty much what you're going to get. Only Millsap is going to need Carlos Boozer to opt out early and leave town to gain a starting role again.

SF/PF Jeff Green, SF/PF Thaddeus Young, PG/SG Rodney Stuckey, F/C Spencer Hawes, C Greg Oden, PG/SG Ramon Sessions

It's hard to tell you to keep any of these players for next year (except maybe Green), since they don't have a strong body of work this year to reassure you and chances are they still need more time to develop. So the Lab will NOT recommend keeping any of these guys in leagues that are focused on winning next year or even the year after, but if you're in it for the long haul, keep these names in mind.

Group 1: F/C Al Jefferson, C Andrew Bynum, PG Gilbert Arenas, F/C Elton Brand

Group 2: G/F Michael Redd, PG Jameer Nelson, C Andrew Bogut, C Chris Kaman, G/F Michael Dunleavy

This tier is separated into two groups. The first group consists of fantasy players who, if you're the gambling type, you could consider keeping for next year given their level of production in the past or promise in the future. There is always the chance that a player, say Arenas, pulls, well, an Arenas, and doesn't recover well from his injury and ends up out most of next year too. If you want to take that risk, Group 1 is where you'll find your keeper. Group 2, not so much. These guys might seem like good keeper options, but they have too many things working against them, with not enough talent to make it worthwhile being at the top of the list.

Group 1: PG/SG O.J. Mayo, C Brook Lopez, PG Russell Westbrook, F/C Kevin Love, SG Eric Gordon, PG/SG D.J. Augustin

Group 2: SF/PF Michael Beasley, PG Mario Chalmers, SF/PF/C Jason Thompson, C Roy Hibbert

Group 3: SF/PF Anthony Randolph, SF/PF Danilo Gallinari, F/C Marreese Speights, PG Jerryd Bayless

Ah, the rookies. The Lab has waited till the end to speak about nearly all of the rookies -- except Derrick Rose -- because they are so volatile and too many leagues have different keeper rules. Some leagues insist on keeping rookies, others have time limits of two or three years before a player gets thrown back into the pool, others are dynasty leagues or without time limits. It's a crapshoot, especially with the rookies' ages varying so greatly, so it makes giving proper advice about the rookies difficult. That's why I've placed them into three groups.

Group 1 is populated by players who will make an impact as soon as next year. Some are already helping fantasy teams as we speak. If you have to keep a rookie, or really want to, this is the group I would choose from, and in the order listed. This is a very deep rookie class, which is why six names are listed in this group (plus Rose is listed above). All of these players figure to having starting spots on their NBA teams and a couple project as fantasy All-Stars --Mayo, Lopez and Westbrook -- with Love trailing closely.

Group 2 consists of players who will probably have to wait another year to make a significant impact. They should improve next year, especially Beasley (who was the second youngest player in the league this year), but he still appears another year away. Chalmers might not have a future at all, but if he can hang with this team, he should be useful. Thompson has impressed everyone who questioned his selection on draft day. If the youth movement keeps on keeping on in Sac-town, Thompson could make an impact as soon as next season. Hibbert had his eyes opened earlier this year and will have to work on becoming stronger and more precise with his footwork. It will probably take him two years to develop that before he can truly be serviceable. To be honest, Group 2 isn't nearly as exciting as Group 3. That's probably how their GMs felt back on that fateful day in late June.

Group 3 has serious superstar potential. Randolph will be a stud in this league. He should be everything Lamar Odom never was, as his intensity is nearly unmatched on the court already. He just needs to harness it. He might even make an impact next year, but as the youngest player in the league right now and with Nelson as his coach, we're giving him two years. Gallinari already has D'Antoni calling him the best three-point shooter on the club. He'll want to get his draft pick and fellow Italian more PT, but it usually takes skinny Euros like him a couple of years to bulk up and adjust to the subtleties of the NBA game. Bayless and Speights are talented youngsters who are simply blocked by All-Stars in front of them. They'll have to fight to earn their time, but they are showing flashes of greatness in their limited minutes. Since they are stuck in their rookie contracts for three or four years, they might not surface till they are moved, though an injury will probably bring them into the limelight before then. Don't keep them, just keep an eye on them. All other rookies aren't worth mentioning at this juncture.

Jason Terry, Mike Miller, Peja Stojakovic, Luol Deng, Jamal Crawford, Josh Howard, Jermaine O'Neal, Tracy McGrady, Shaquille O'Neal, Lamar Odom, Jason Richardson, Manu Ginobili, Zydrunas Ilgauskas, Emeka Okafor, Andrei Kirilenko, Richard Jefferson, Ron Artest, Mike Bibby, Rasheed Wallace, T.J. Ford, Randy Foye, Marvin Williams

Don't be fooled. These guys are not keeper-worthy! They may tempt you, but you should avoid them at all costs. Have faith in the Fantasy Lab.

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