September isn't just that awkward overlap month of fantasy baseball and football, it's also the time for baseball rosters to expand. The minor league seasons are ending, and the big clubs want to see what their youngsters can do. For those teams comfortably in first or last, they will give the newbies more at-bats and innings. For those in hot pennant races, they're more likely to see time on travel days or as pinch hitters and mop up relief. For us fantasy players, we just want someone who will give us seven home runs or four wins in September.

Below are some of the callups and what you should expect in September and beyond (that sounded kind of ominous, didn't it?).

Humber swam upstream against the Johan Santana current from the Mets to the Twins. At Rochester, he was a middling 10-8, with a mediocre 4.56 ERA and a pedestrian 106 K against 49 BB and 145 hits in 136.1 IP. You can tell I have my thesaurus open. Regardless, he is a starter who can eat innings. But in a close race with the White Sox, the Twins don't want innings eaten. To his credit, he has pitched better as of late, but Humber is not worth picking up, and with a flush rotation, he's likely not a keeper, either. AL-only players should monitor his progress, though. And for all you Kevin Mulvey fans, he's about the same as Humber, but without the callup.

Knight is back from Beijing and ready to start. However, he likely will see time in the bullpen, which is the area of higher concern for the Mets right now. Knight has had 55 Ks against 12 BBs in 43.1 IP in the PCL, which is good work in a hitter's league. Back in July he made a spot start for the Mets, looking mediocre against the Cardinals. However, he's worth a pick up in the more competitive NL-only leagues and a keeper for 2009. If anyone (else) gets hurt in the Mets' rotation, mixed leaguers should consider picking him up.

The 23-year-old McDonald has made a nice climb from AA to AAA to MLB, and has had solid strikeout numbers. In four starts at Las Vegas he has thrown more than a strikeout per inning (but only two in his last two starts), and has a 4.0 K/BB ratio. However, McDonald is still gaining strength, and is a skinny 195 lbs on a 6-5 frame. As much as everyone is dismissing him as a middle reliever for September, just think about the state of the Dodgers' rotation (Jason Schmidt just got shut down for the season). I'd be surprised if he didn't get a start or two. For very desperate NL-only teams, pick him up. For the rest of the NL-only leagues, wait until he gets a start to pick him up. And for keepers, he's not worth saving unless he has two really good starts.

McDonald's main competition for spot starts in September will be Stults, with the decision likely coming down to whether the opposing team can hit lefties or not. Or at least one hopes the Dodgers use some type of logic in making the decision. Stults' AAA numbers weren't quite as good as McDonalds', but Stults had 11 more starts than McDonald, so the former's data is more reliable. Stults's stint in the majors this year included a complete game shutout of the White Sox, which could put him ahead of McDonald. I say there's room enough for both, but like McDonald, just monitor whether he starts and how he does.

They say the balls fly really far, off Broadway (off Broadway ...). At Charlotte, Broadway's numbers aren't anything to sing about (OK, I'll stop), but what could make him a good pitcher in the South Side is his GO/AO ratio of 1.65. However, when he has pitched for the White Sox, he hasn't missed many bats. Perhaps that throttling was enough to shake the butterflies, but whether Broadway can get his confidence back is less important than whether he can get Ozzie Guillen's confidence back. Odds are he can't, and will see mop up duty in September. And unless he magically turns into Brad Lidge (the good one, not the bad one), he isn't worth keeping, either.

We've seen Cassel's work before, and frankly, we're not impressed (that's the royal "we"). He started four games in '07 and has started three this year, so it's only by technicality that we include him as a callup. However, that 7.11 ERA looks better on a lottery ticket than a baseball card, so just let this one go.

Parr is another player who started the year in AA and has now made it up to the bigs. His numbers improved slightly in his 10 starts in AAA, versus his 17 starts in AA. Parr will likely see a start or two, but at 22, he's a year or two away from showing what he can do. Right now his numbers mumble "good, but not great," so watch him this September. But since the Braves' rotation will see lots of turnover this season, consider picking him up as a keeper if he can put together two good starts.

Baseball is all about second chances, and if you're a southpaw starter, you'll get as many chances as you want. O'Connor was Washington's minor league pitcher of the year in '05, started 20 games for the Nationals in '06 and looked good, but not great. This year he has thrived in the International League, with a 1.00 WHIP and a 2.17 ERA, but spilled his cup of coffee with the Nats in late April/early May. Once again he gets the call. It will be hard for him to show that he's anything more than a AAAA pitcher, and he should not be picked up. But keep an eye on his results as sometimes lefties take longer to figure out pitching than righties.

So while you monitor O'Connor, watch Martis even closer. He has amassed a strikeout an inning in AAA, has a K/BB of about 2.5. The worst part about his pitching is that he's doing it for Washington, but watch anyway as sometimes we find aces in the weirdest places. And as much press as Tyler Clippard has gotten, Martis is looking like the better pitcher.

I'm still not sure what the Blue Jays have against Canada, but they brought Richmond up during the Olympics, which prevented him from wearing the Leaf for his country. After he compiled an ERA over 5.00, they sent him down. Now, they're bringing him up again. Richmond is a little old for all this rookie business (he just turned 29), and his numbers at Syracuse were only decent. Considering where this team is right now, Richmond is not worth picking up.

How you doin'? I thought LeBlanc had the fifth spot all sown up coming out of Spring Training, but the Padres gave it away to Justin Germano. Considering how the team has done this year, perhaps they should have gone with the southpaw. LeBlanc has shown good control (139 K in 138.2 IP, 3.31 K/BB), but the rest of his numbers have been mediocre. What's most worrisome -- his 0.67 GO/AO ratio -- could be absorbed by Petco Park, the place where bats go to die. In competitive NL-only leagues, pick him up. In other NL-only leagues, see how he does in his first couple of starts. Either way, he could be a sleeper/keeper, which is pretty cool as it rhymes. And yes, this is all based on the assumption that '08 was the aberrant year for the Padres, not '07.

Moseley had 10 starts over '06 and '07, and went 5-3, which put him ahead of Nick Adenhart as the Angels' fifth starter out of spring training. He then got hit hard and was sent to the bullpen. Then he hit the DL with a strained forearm, rehabbed in Salt Lake City, got called up for a spot start (which went well) and went straight back to Salt Lake. Now he's back in Anaheim, but the rotation is set and word is Moseley is set for mop up duty. However, I'm going to go counter to conventional wisdom and say Moseley sees a couple of starts for a Angels' team that will rest up for the playoffs, and I'll even go so far as to say he's a keeper for '09. There. That's the way you end a column.

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