A couple of rookie relievers have actually had better seasons than Feliz in 2010, but no one can match his upside. Feliz has a fastball/breaking ball combo that's at the top of the scouting scale, and his changeup was developing nicely back in his days as a starter. As for his role in the future, there's little doubt he could be a shutdown reliever for years to come, but it's possible the Rangers will return him to a starting role at some point. For now, though, he's the best young reliever in baseball.

Also worth mentioning: Daniel Bard, Red Sox; Drew Storen, Nationals

Price has a devastating power arsenal, and this season his performance has risen to meet the hype. He ranks second in the AL in ERA and was recently named to the actual All-Star team. That's just what the Rays were hoping for when they made him the No. 1 overall pick of the 2007 draft. Barring injury, he'll be a frontline ace for years to come.

Also worth mentioning: Brett Anderson, A's; John Danks, White Sox; Jaime Garcia, Cardinals; Clayton Kershaw, Dodgers; Brian Matusz, Orioles; Ricky Romero, Blue Jays

Whither Stephen Strasburg? Sure, Strasburg has a higher ceiling than any pitcher in baseball, but presenting him this honor would be a tad premature. So, consider him the early favorite for 2011. As for King Felix, it's easy to forget that in the B.S. (Before Strasburg) epoch, it was Hernandez's potential that was exhausting the superlatives. He boasts four plus-to-plus-plus pitches, shows exceptional command and keeps the ball on the ground. Throw in a generally positive health history, sound mechanics and a good pitcher's frame, and you've got an elite hurler. He turned in a Cy Young-caliber season in 2009, and he's thriving again in 2010.

Also worth mentioning: Chad Billingsley, Dodgers; Clay Buchholz, Red Sox; Matt Cain, Giants; Yovani Gallardo, Brewers; Tommy Hanson, Braves; Phil Hughes, Yankees; Jair Jurrjens, Braves; Mat Latos, Padres; Mike Leake, Reds; Stephen Strasburg, Nationals

During the run-up to the 2005 draft, you heard quite a few scouts call Upton the best high school talent since Alex Rodriguez in 1993. Mostly, that was because of Upton's jaw-dropping bat. He thrived in the high minors despite being much younger than his peer group. At Arizona last season, he hit .300 AVG/.366 OBP/.532 SLG and made the All-Star Game as a 21 year old. His overall numbers this season are down a bit (though not for a player his age); however, he's coming off a lava-hot June, and he figures to be among the NL's most productive players the rest of the way. He's a future MVP candidate.

Also worth mentioning: Jay Bruce, Reds; Matt Kemp, Dodgers; Carlos Gonzalez, Rockies; Adam Jones, Orioles; Andrew McCutchen, Pirates; Travis Snider, Blue Jays; Delmon Young, Twins

Among 25-and-unders with a qualifying number of plate appearances this season, Rasmus has the highest slugging percentage (by a comfortable margin) and the most home runs (by a narrow margin). Indeed, he's in the midst of a breakout season, and that's no fluke. Great range in the outfield, powerful arm, powerful bat, advanced pitch recognition, patience at the dish - the guy's got more tools than a frat house. The comparisons to Jim Edmonds are justified.

Sam Perkins should totally cede the nickname "Big Smooth" to Heyward because the latter embodies the spirit of being both "big" and "smooth" much better than almost anyone in the history of history. Coming into the 2010 season, most prospect lists had Heyward ranked ahead of Stephen Strasburg, so that gives you some idea of his limitless potential. Heyward boasts light-tower power from the left side, plate discipline far beyond his years, plus range in right field and an exceptional attitude and work ethic. He's on the DL right now, and he slumped badly in June. However, he'll one day be known as the best hitter in baseball. That's more than enough to earn him a spot on this team.

Tulo's one of the best defensive shortstops in baseball, and - now that Derek Jeter is in his decline phase - he's the best hitting shortstop not named Hanley Ramirez. Tulowitzki's sidelined with an injured wrist at the moment, but once he returns he'll look to build upon this season's batting line of .306/.375/.502. When healthy, he's one of the NL's best overall players.

Also worth mentioning: Elvis Andrus, Rangers

Lots of competition at the hot corner, but Longoria edges out D.C.'s Ryan Zimmerman. Longoria has loads of raw power, command of the strike zone, the ability to hit for average and Gold Glove skills in the field. Combine all that with an exceptional minor-league pedigree, and you've got a rare talent. This season, he's on pace for 80 extra-base hits, which would be the fifth-highest total ever for an American League third baseman. The over-under on career MVPs: 1.5.

Also worth mentioning: Pablo Sandoval, Giants; Ryan Zimmerman, Nationals

Before you flip out, consider that the population of 25-and-under second basemen who, a) have upside and, b) are thriving in 2010, is quite small. This spot would probably belong to Gordon Beckham were his 2010 numbers not so patently awful. Alas and alack ... As for Rodriguez, he's hitting .276 AVG/.310 OBP/.438 SLG, which is respectable enough for a middle infielder toiling in the brutal AL East. Rodriguez hit quite well coming up through the minors (29 homers across three levels in 2006), and he's now part of an organization that knows a little something about cultivating young talent. Obviously, though, this is the soft underbelly of the 25-and-under team.

Also worth mentioning: Gordon Beckham, White Sox

Butler isn't much with the glove, but his bat is legit. This season, he's hitting .320 and on pace for 48 doubles, and he just recently became the youngest active player to get to 500 career hits. Given his underlying skills (he was the 14th-overall pick of the 2004 draft and a career .336 AVG/.416 OBP/.561 SLG hitter in the minors), those numbers are justified. Don't be surprised if he contends for the batting title the next five years or so. On the other hand, he could improve his standing if he'd go by his awesome full name of Billy Ray Butler.

Also worth mentioning: Ike Davis, Mets

Until Matt Wieters begins to think about considering the possibility of approaching something resembling the hype, Santana owns the honor of top catcher under the age of 25. Coming into the season, Santana was, by force of consensus, a top-10 prospect, and since his belated call-up he's put up a batting line of .300 AVG/.438 OBP/.600 SLG. He probably won't sustain those numbers, but they aren't terribly out of line with how he should produce during his prime seasons. Your move, Wieters.

Also worth mentioning: Buster Posey, Giants; Matt Wieters, Orioles