It's March, and that means draft season is officially upon us. Sure, we in the field have been conducting mock drafts for a while now, and while some of those get played out, they're mainly an exercise to show off current trends in draft and auction rooms across the industry. Now it's time to take what we learned in February and put it into practice.

The most important thing to consider is value. Each pick you make, no matter if its your first or your last, comes with an opportunity cost, the price you pay for not taking a certain player. So if you have to make a tough choice, say Rickie Weeks or Justin Upton (who are separated by just 0.16 spots in average draft position), you can't just compare the players at face value. You also need to consider the relative value of these players. If you grab Weeks, you have one more outfield spot to fill later. If you tab Upton, you'll still be looking for a second baseman, and he'll probably have to come at a much later point in the draft. In a draft or auction opportunity cost rules all.

That's why knowing a player's average draft position is so instructive heading into your draft. The folks at Mock Draft Central do a fantastic job aggregating all of their drafts and putting out a top 200 list by ADP. They also host a ton of expert drafts, and offer separate ADP reports comprised of only expert picks.

Heading into draft season, let's look at some of the most overvalued and undervalued players. Who should you avoid at the current market price, and when can you get bargains?

Joe Mauer (ADP: 20.15, Expert ADP: 23.9) -- I've covered both Mauer and catchers overall pretty extensively, but it bears repeating. Unless 1970 Johnny Bench comes walking through that door, there's no reason to grab a catcher early in a one-catcher league. I know Mauer's batting average and OBP numbers will be a huge boon to those in rotisserie leagues over a full season, and a presumed return to health for Justin Morneau should give the catcher some much-needed protection. Still, when the names getting called around Mauer include Chase Utley, Prince Fielder, Tim Lincecum and Ryan Zimmerman, taking Geovany Soto in the 10th or 12th round looks a whole lot more attractive.

Brandon Phillips (ADP: 34.78, Expert ADP: 35.1) -- There's an episode of Curb Your Enthusiasm in which, at the urging of his psychiatrist, Larry David takes his wife Cheryl to the beach. Once there, he predictably begins complaining, saying he doesn't understand what people love about the ocean. Cheryl explains its charms of relaxation, and asks if Larry feels the same. "No," he replies. "I feel aggravated that I'm missing what other people are getting."

I feel the same way about Phillips. What am I missing? Since going 30-30 in 2007, Phillips has seen his home run total fall to 21, 20 and 18 last year. He bottomed out at 16 stolen bases last year, despite playing 155 healthy games. Last season was his best in terms of OBP, when he got on base at a blistering .332 clip. In '07, his ground ball rate was 46.7 percent and his line drive rate was 18.5 percent. Last year, those numbers were 51.4 and 15.3. This is a guy I want to use my third pick on? Is it because second base is an ostensibly shallow position? Because if that's the reason, you need to take another look. Ian Kinsler is the seventh-ranked second baseman in terms of ADP. Kelly Johnson, who hit 26 homers with 13 steals and a .370 OBP last year, is going 80 picks after Phillips. I'll pass on Phillips in every draft I'm in this season.

Mariano Rivera (ADP: 61.12, Expert ADP: 85.9) -- Here's where the everyday fantasy players can truly learn a lesson from the experts. Unless you are in a saves only league, you should never, no matter what, pay a premium for saves. Don't believe me? Here's a list of the 10 relievers with the most saves last year, along with their ADP:

Brian Wilson -- 48 saves, 135.19 ADP Heath Bell -- 47 saves, 97.03 ADP Rafael Soriano -- 45 saves, 148.97 ADP Joakim Soria -- 45 saves, 98.03 ADP Francisco Cordero -- 40 saves, 102.48 ADP Neftali Feliz -- 40 saves, 183.11 ADP Carlos Marmol -- 38 saves, 134.67 ADP Kevin Gregg -- 37 saves, 376.12 ADP Jonathan Papelbon -- 37 saves, 65.41 ADP Billy Wagner -- 37 saves, 137.68 ADP

Just as many of the guys above were drafted outside the first 144 picks (also known as the first 12 rounds in a 12-team league), as were in the top 100. I repeat: There is no reason to pay for saves. Do not be the first person in your league to take a closer. You will be ridiculed and it won't be fun. But you will deserve it.

Elvis Andrus (ADP: 71.36, Expert ADP: 62.9) -- A guy who has posted a .266/.336/.333 slash line with a grand total of six homers across two seasons going this high smacks of drafters being at the mercy of positional scarcity, a consideration you have to be careful to take too far. Otherwise, you'll end up with Andrus in the fifth or sixth round. Yes, the steals are nice. Unfortunately, Andrus doesn't get on base at a respectable enough rate to hit at the top of the Rangers' order, and thus take advantage of hitting in front of Josh Hamilton, Nelson Cruz and Adrian Beltre. At this price, you can get a stud pitcher like David Price or Justin Verlander, or a multi-tooled outfielder like Hunter Pence, all better options than a powerless rate-killer like Andrus.

Kevin Youkilis (ADP: 30.9, Expert ADP: 31.4) -- Going right around 30th overall, there isn't much room for Youkilis to move up. Still, we're talking about a guy who you can bank on for a .300 batting average and .400 OBP. He was well on his way to his third straight season of at least 27 homers last year before a hand injury cost him 60 games. In the last three years, his worst OPS has been .958. He plays in a lineup that added Carl Crawford and Adrian Gonzalez. And two weeks into the season, he'll gain eligibility at third base, one of the shallowest positions on the board this year. All reports on his hand are positive, so there's no reason to expect any lingering effects. Youkilis is regularly going behind Joe Mauer, Jose Reyes, Nelson Cruz and Shin-Soo Choo. That simply should not be the case.

Colby Rasmus (ADP: 93.87, Expert ADP: 85.7) -- While this hasn't been the best offseason in St. Louis, the Cardinals are no doubt excited for the third year of the Colby Rasmus era. Rasmus struggled getting on base his rookie season, hitting just .251 with a .307 OBP. But he showed flashes of power, belting 16 homers and 22 doubles. He took a major step forward last year, hitting .276 with a .361 OBP and 23 home runs. He even threw in 12 steals for good measure. Now, with two full seasons under his belt, he's poised to take another leap. Rasmus doesn't turn 25 until August, so chances are he's still developing power. You should be able to grab him in the range of 90th overall, which will be an absolute steal come September.

Shaun Marcum (ADP: 109.41, Expert ADP: 150.2) -- We've seen the script before. American League pitcher moves to the National League, remains essentially the same guy, yet his stats become a whole lot prettier. It happened with Bronson Arroyo. It happened with Ted Lilly. With all due respect, neither of those guys are pitchers the caliber of Marcum, who isn't just leaving the AL but the AL East. Last year, Marcum made six starts, a full 20 percent of his outings, against the Red Sox and Yankees, the top two teams in terms of OPS last season. He's trading them for the NL Central, which features the Cubs (19th in team OPS last year), Pirates (28th) and Astros (29th). He's got a five-pitch repertoire, relying on his changeup and cutter as plus-pitches. If he stays healthy, 200 strikeouts is not out of the question.

Drew Stubbs (ADP: 167.38, Expert ADP: 127) -- Let's get the bad stuff out of the way first. Stubbs strikes out too often, fanning in 32.7 percent of his at-bats last year. On its face, his .330 BABIP seems high. OK, are you ready for the good stuff? Let's start with that BABIP. In four minor league seasons (including a year of Rookie League ball), Stubbs never had a BABIP lower than .333. In about one-third of a major league season in '09, his BABIP was .325. It's early in his career, but it appears a higher-than-average BABIP may just be part of Stubbs' skill set. His 30 steals from last season look like a floor, as he stole 121 in 423 minor league games (including 46 in 107 games at Triple-A in '09). His 22 homers appeared to come from nowhere, and his line drive percentage (15.5) and fly ball percentage (40.5) weren't especially high. But he did post an ISO (isolated power, calculated by subtracting batting average from slugging percentage) was .189, well over league average. At 25 years old (he turned 26 right after the season ended), there is a chance Stubbs found a power stroke last season. Stubbs looks like a potential 25-30 guy just sitting in the bargain bin waiting to be scooped up. With outfielders like Alfonso Soriano and Vernon Wells going in the top 100, Stubbs is criminally undervalued.

Chat with me 140 characters at a time on Twitter, @MBeller.

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