Orlando Cabrera, SS The Reds' shortstop typically gets a pass on his hitting -- this year sinking to new lows with a .245 average and .283 OBP -- because of his slick glove. But this year he's only been a slightly above-average fielder this year, with a 3.1 UZR/150, which is a measure of Ultimate Zone Rating prorated to 150 games, or about what most starters play during the season. In 2009 he had a -12.1 UZR/150, meaning he's slowed a step from some of his more spectacular seasons earlier in his career. He could be pushed for playing time by reserve infielder Paul Janish, who has a .397 OBP in 30 games.
J.A. Happ, SP Happ had a dazzling rookie season last year in which he went 12-4 with a 2.93 ERA, but he has missed most of 2010 with a forearm strain. He was on pace for a midsummer return but struggled so much in his minor-league rehab appearances -- a 6.67 ERA in seven outings -- that the Phillies have kept him in Triple-A for now. But the major-league club needs need at least one addition to their starting staff to replace the ineffective Joe Blanton and, having failed (or opted not to try) to land Cliff Lee for the second straight summer, Happ is the best in-house answer. Should he continue to falter, the Phillies could look to brining back free-agent Pedro Martinez, the self-proclaimed "old goat" who was successful for them in last year's playoff run.
Carlos Beltran, CF When healthy, Beltran is one of baseball's best all-around players, and in 2004 he was the most important trade deadline acquisitions, when he was dealt to the Astros and helped them reach the playoffs. He'll again be one of the game's most important midseason additions, with the potential to lead the Mets to the playoffs, only this time he's rejoining his current team after undergoing major offseason knee surgery. It's unclear how much he'll be able to play -- starting two out of every three games would be a good guess -- but he'll still force the hand of manager Jerry Manuel, who will have to decide how to platoon his other three outfielders. Angel Pagan has played the best, while Jeff Francoeur is great defensively but is wildly inconsistent at the plate and Jason Bay has underwhelmed.
Pablo Sandoval, 3B The Panda was one of baseball's best hitters in 2009 (.330 average, 25 home runs, 90 RBIs) and has been one of its most disappointing in 2010 (.263, six HR, 34 RBIs). He even leads the NL for having grounded into 19 double plays. The Giants' offense was already shaky when he did produce, so having him slump has been difficult for them to overcome.
Tyler Greene, SS Greene is only as important for who he is not, Brendan Ryan. As the backup shortstop, Greene, who started six of the final seven games before the All-Star break, is a breath of fresh air compared to Ryan, who has an amazingly low OPS+ of 48. Ryan doesn't have quite enough plate appearances to qualify for the batting title, but if he were to reach that threshold, he would be only the 18th player since 1950 with such a low number.
Joe Mauer, C Mauer's production is way off from his AL MVP season of 2009, when he batted .365/.444/.587, leading the league in all three categories, while establishing career highs with 28 home runs and 96 RBIs. This year, Mauer is batting .293/.368/.424 with just four home runs and 35 RBIs. The Twins, who were so great in April and May, have slipped to third place in the AL Central and need more power from Mauer and Michael Cuddyer, who has just nine homers after hitting 32 last year.
Mike Napoli, C/1B With Kendry Morales lost for the season with a broken ankle, first base could go from strength to weakness for the Angels, depending on what Napoli, primarily a catcher, can produce at the position. Napoli has hit 20 home runs each of the past two seasons without reaching 400 at bats either year, because his shortcomings as a catcher kept him in a platoon. At first he has the chance to play nearly every day.
Yunel Escobar, SS Manager Cito Gaston has one last large chore before leaving the dugout at the end of the season: help get newly-acquired shortstop Yunel Escobar back on track offensively. Escobar, whom Toronto got from Atlanta in a trade Tuesday, is a player with great potential, and because the Blue Jays are rebuilding this season, they can afford to be patient with him. Over the past two seasons with the Braves, Escobar averaged hitting .293 with 12 home runs and 68 RBIs, but he has zero homers and 19 RBIs this season.
Mike Stanton, RF As a scout said about the Marlins just before the break, "They could get back into it because they have pretty good starting pitching." But Florida will need more pop if it's going to challenge seriously for the playoffs, and the highly touted rookie Stanton may need to carry that load. So far he's shown moderate power -- 11 extra-base hits, including five homers, in 108 at bats -- but little plate discipline, with just seven walks and a .276 OBP.
Brett Anderson, SP Oakland's dalliance among the AL West leaders is over, so the focus is about developing its young pitchers. In Anderson's case, part of that is simply to prove he's healthy, as returning to the majors this season will give him a confidence boost going into the offseason. His first six starts were great (2-1, 2.35 ERA, just four walks in 30 2/3 innings) before left elbow inflammation sidelined him. At one point it was thought to be serious enough to require surgery. He and All-Star Trevor Cahill have the makings for a great 1-2 punch the next several years.
Get expert analysis, unrivaled access, and the award-winning storytelling only SI can provide—from Peter King, Tom Verducci, Lee Jenkins, Andy Staples, Grant Wahl, and more—delivered straight to you, along with up-to-the-minute news and live scores.