Whatever the reason, teams do themselves and their fans a disservice by not putting the best players on the field. So with that in mind, let's take a look at five contending and kinda-sorta contending teams that need to make certain personnel changes in a hurry. If they want to stick around in the race, that is.

Cincinnati Reds, CF

Out: Corey Patterson
In: Jay Bruce

If you were previously familiar with Dusty Baker's long-standing fetish for veterans, then the decision to give the center-field job to Patterson coming out of spring training was hardly shocking. Patterson started out strong this season, but now he's authoring a listless (and customary) batting line of .213 AVG/.281 OBP/.475 SLG. The power numbers aren't bad (keep in mind they're inflated because of his home park), but that .281 OBP is patently unacceptable, especially for a leadoff hitter. As for Bruce, the top prospect in all of baseball, he's hitting .322 AVG/.347 OBP/.567 SLG at AAA-Louisville, and those numbers are very much in keeping with his established level of performance. He's more than ready for starting duty at the highest level. Patterson's a perfectly useful fourth outfielder, but he's far and away Bruce's inferior. If the Reds are serious about getting back in the NL Central race, they need to make this change posthaste.

Los Angeles Dodgers, 3B

Out: Anyone other than Andy LaRoche
In: Andy LaRoche (when healthy)

LaRoche (thumb) is presently on a minor-league rehab assignment, but he should be ready to come off the DL by mid May. When he does, he should be installed as the Dodgers' every-day third baseman and left alone. To be sure, the Dodgers have other options, but none of them figures to provide as much as LaRoche. The injured Nomar Garciaparra? He's no longer a productive hitter and no longer able to handle the position defensively. Blake DeWitt? He hasn't produced above the low minors and can't approach LaRoche's upside. LaRoche, meanwhile, is a career .295 AVG/.374 OBP/.522 SLG hitter in the minors, and he has the skills — raw power, command of the strike zone, contact skills — to keep it up in L.A. Third base was a sinkhole for the Dodgers last season, and LaRoche gives them the best chance to fill said sinkhole.

New York Yankees, fifth starter

Out: Ian Kennedy or Mike Mussina
In: Joba Chamberlain

The recent woes of Kennedy and Philip Hughes have been heavily chronicled. The obvious solution is to bump Kennedy, the less promising of the two struggling youngsters, in favor of Chamberlain. The concerns, of course, are that Chamberlain would leave a gaping void in the bullpen and might injure himself under a starter's workload. Those are legitimate frets, but they aren't enough to outweigh the benefits of moving Chamberlain into the rotation.

Kennedy is potentially a solid major-league pitcher, but he's overrated by the multitudes of Yankee homers. He's got the exceptional changeup going for him, but the rest of his repertoire doesn't impress. In particular, his fastball, which lacks movement and is merely average in terms of velocity for a right-hander, could be a problem for him going forward.

Rather bump Mussina? Fine, although he's been much better than Kennedy to date. The prevailing point is that someone not named Chien-Ming Wang or Andy Pettitte needs to make way for Chamberlain. Speaking of Chamberlain, his fastball and power breaking ball are off the charts, and he's got a workable change. As for those health concerns, he hasn't had any serious ones since his final season at Nebraska, so perhaps it's time to stretch him out. He's got the makings of a frontline starter in the majors, and that's precisely what the Yankees need. Yes, he'd leave a hole in the pen, but let's be reasonable about this: You'd rather have a thin middle-relief corps than a thin rotation.

Cleveland Indians, closer

Out: Joe Borowski (when healthy)
In: Rafael Betancourt

Last season, Borowski may have led the AL in saves, but that doesn't mean he was any good. Borowski in 2007 posted an RA (runs per game) of 5.34, and, in a related matter, right-handed batters slugged a robust .484 against him. This season, he's been utterly awful, but the sample size is so small as to be meaningless. Borowski is presently on the DL with arm trouble and is slated to return by the middle of May. Once he does get back, the Indians should dispatch him to middle relief. Betancourt is a much better pitcher than Borowski, and it's an inexcusable mistake to give your high-leverage relief innings to a pitcher like Borowski, who has nothing but the overly mythologized "closer" tag going for him.

St. Louis Cardinals, SS

Out: Cesar Izturis
In: Brendan Ryan

The Cardinals aren't going to get good numbers from shortstop this season no matter who's manning the position. However, Izturis simply isn't a major-league hitter. For his career, he's a career .258 AVG/.297 OBP/.332 SLG hitter (he's been even worse thus far in 2008), and his defensive merits can't even begin to make up for such a lack of production. Ryan, meanwhile, is a capable defender at the position and, unlike Izturis, he actually has something resembling offensive upside. An optimal solution he's not, but Ryan constitutes a substantial improvement over Izturis.