Fantasy Baseball Sleepers 2012: Developing Players Guaranteed to Become Stars

Taking a chance on an unproven player often doesn't pay off. At least with me, it seems that the simple fact that I pick a player causes him to play terribly that season.

But when you make the right choice on a player who's still developing, but turns out to be one of the top players at his position, the payoff can be huge. It's just important to focus on the players who seem to be trending up, instead of picking players who have been highly touted, but are taking too long to develop or aren't improving at all.

Here are a few that seem to be on the upswing as we approach the 2012 season.

Danny Duffy, LHP, Kansas City Royals

He struggled a bit during his rookie year in 2011, but is one of very few starting southpaws whose fastball is clocked at 95 mph or more. He made 20 starts last year, logging 105 1/3 innings with a 5.64 ERA, 4.4 walks per nine innings and 7.4 strikeouts per nine.

However, because both of those numbers are far worse than his career minor league averages, it's reasonable to suggest he's still adjusting to the major leagues.

Duffy has an above-average curveball and the potential to be a No. 1 pitcher a few years down the line. For now, he's still a solid pick and is projected to make 27 starts with a 4.40 ERA and 8.09 K's per nine innings.

Giancarlo Stanton, OF, Miami Marlins

He possesses the kind of power that can be lethal as he continues to develop in the majors—his average home run last season measured 417 feet, the third-most in the majors. Therefore, you certainly shouldn't worry that he'll be adversely affected by the Marlins' new park; it probably will favor him.

Last year, in 516 at-bats, he hit 34 homers with 87 RBIs, a .537 slugging percentage and a .893 OPS.

Stanton's numbers are only expected to increase next year, though not by a colossal amount. His average should stay nearly the same, with a few more homers and 100 or more RBIs. Be aware of his strikeout totals, though: He had 166 in 150 games last season.

Brett Lawrie, 3B, Toronto Blue Jays

He had 150 at-bats last year and hit nine homers, slugged .580, had a .953 OPS and batted .293 overall. Lawrie didn't start in the bigs to start 2011 because the team thought he needed some more work defensively, and a fracture in his left hand in late May delayed his arrival even further. Once he did come up on August 4, though, his value was immediately apparent.

He makes good contact and has power and speed, and with more at-bats this season, his average and OPS are projected to decrease a bit—but he still should be good for 20-plus home runs and 70 RBIs. Just account for the fact that he still needs time to adjust to a full season in the majors.