The best players to build a team around (cont.)

At 14-9 with a 2.64 ERA and eight complete games, Roy Halladay is in contention for the Cy Young award yet again. AP

No. 39. Roy Halladay, P, Blue Jays, Age 31 (No. 25)

He loses a little bit of position on this list each year as he ages, but one thing that augers well for his future is his pitch efficiency, as he's required just 3.60 pitches per plate appearances this season. Halladay may be the closest thing we have right now to vintage Greg Maddux.

No. 38. Mark Teixeira, 1B, Angels, Age 28 (No. 45)

Maybe he just requires a mid-season trade every year to really get him going. Teixeira differentiates himself from your ordinary slugger because of his outstanding defense, which has already won him two Gold Gloves and deserves more. As an aside, the word 'Teixeira' now appears in the Microsoft Word spell-check dictionary because of a complaint I made in the originial version of this column.

No. 37. Rich Harden, P, Cubs, Age 26 (HM)

We said at the outset that this list is all about upside. So I'm willing to accept some injury risk for pitchers -- provided that they can be this good when healthy.

No. 36. Lance Berkman, 1B, Astros, Age 32 (No. 32)

I had to think carefully about whether I was overrating older first basemen after getting burned badly on David Ortiz and Travis Hafner from last year's rankings. But his pudgy appearance aside, Berkman is a notably better athlete than either of those guys ever were, and he certainly has had no trouble with the stick.

No. 35. Prince Fielder, 1B, Brewers, Age 24 (No. 47)

Prince's power stroke has fully returned after getting off to a little bit of a slow start this season, perhaps because of the vegetarian diet that he adopted over the winter. Let's hope that staying cheeseburger-free will help Prince to trim down a bit, because as good as his bat is, this body type doesn't lend itself to long careers.

No. 34. Nick Markakis, RF, Orioles, Age 24 (--)

Believe it or not, the Orioles actually placed two young hitters in the Top 50, and another into Honorable Mention. Markakis is probably never going to be a huge power hitter, but with a great line-drive stroke and an even better batting eye, he'll be a top-of-the-order hitter for years to come.

No. 33. Jimmy Rollins, SS, Phillies, Age 29 (No. 48)

So who's the real Jimmy Rollins? Last year's MVP version, or the merely good player that he's been this year? Actually, I don't think this is all that difficult to resolve: Rollins is a very good player who had a career year, which happens not infrequently when a player is near his age 26-28 peak.

No. 32. Matt Wieters, C, Orioles, Age 22 (--)

Here is the other Oriole -- and the only current minor leaguer to make our Top 50. Since last season, we have significantly revised our minor league forecasts to make them more conservative ... but Wieters still blows the system out of the park, with a 1.038 OPS thus far on the season in spite of playing in some pitcher-friendly environments. Wieters might be in the upper quartile of major league catchers if he put on an Orioles uniform right now -- and he's only 22.

No. 31. Dan Haren, P, Diamondbacks, Age 27 (--)

Here's a guy who just really understands how to pitch, mixing in fastball, spitter and slider in perfect ratios. PECOTA likens him to a young Curt Schilling, which sounds just about right.

No. 30. Ryan Zimmerman, 3B, Nationals, Age 23 (No. 11)

Like nearly everyone else in Washington -- and I don't just mean the Nationals -- he's had an off year. But let's look at the resume: a bat that was good enough to be considerably better than league average by the time Zimmerman was 21 ... Gold Glove-caliber defense that still goes underappreciated ... his star has dimmed just a bit, but Zimmerman is still a franchise player.

No. 29. Ian Kinsler, 2B, Rangers, Age 26 (HM)

His profile is starting to look a little bit like vintage Jeff Kent, a fellow late bloomer who had always projected as a decent bat, and then wound up being a borderline great one. In fact, Kinsler is a considerably better athlete than Kent and also plays superior defense. Just keep him away from pick-up trucks.

No. 28. Joba Chamberlain, P, Yankees, Age 22 (--)

PECOTA tends to be extremely conservative with young pitchers, but before the year began, it had Joba rated as the No. 2 prospect in baseball, trailing only Evan Longoria. In spite of all the consternation about whether he should start or relieve, and in spite of his presently being on the disabled list, Chamberlain has really done everything to live up to PECOTA's expectations, having stuck out 10.5 batters per nine innings. Joba does feel like he might be the case where the star that burns twice as bright burns half as long, so I don't necessarily expect a 15-year career, but I do expect some outstanding performances over the next half-dozen seasons.

No. 27. Matt Holliday, LF, Rockies, Age 28 (--)

His career batting marks away from Coors Field are a .280 batting average, .346 on-base percentage, and .459 slugging average, which is pretty close to league-average for a corner outfielder. But a player should not be punished just because he happens to have adapted himself exceptionally well to his home environment, and Holliday is an underrated defender -- something that would play well just about anywhere.

No. 26. Russell Martin, C, Dodgers, Age 25 (HM)

This is really one of the half-dozen most unique skill sets in baseball, with significantly above-average speed for a catcher, Gold Glove defense, and an outstanding plate approach. But a lot of Martin's value stems not from the fact that he plays better than other catchers so much as that he plays so much more than other catchers. It is exceptionally rare for a catcher to work his way into as many as 150 ballgames in today's environment, yet Martin did that last year and he should be on pace to do it again this year, even if occasionally has to cheat by playing third base.

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