As teams approach the 81-game milestone that marks the official midpoint of the season, it’s becoming increasingly clear that some of last winter’s best-laid plans have already gone awry. However, it’s often not the presence of an underperforming player that defines a team’s season, but how the team attempts—or fails to attempt—to correct that weakness. Clubs that content themselves with subpar production for too long run the risk of finding themselves excluded from October, while those that respond proactively can salvage a season before it runs off the rails.

Some teams have already acted to address an obvious deficiency. After watching Jack Hannahan hit .171/.272/.240 since May 4 and backup Adam Everett hit .217/.277/.233 on the season, the Indians decided not to let cold bats at the hot corner sink their surprising season, and called up top prospect Lonnie Chisenhall to fill the offensive void on Monday. Some other clubs still suffering from counterproductive contributions could learn from the Indians’ example.

The least productive position in baseball this season has been first base in Baltimore, where Derrek Lee and an assortment of part-timers led by Luke Scott and Brandon Snyder have combined to play nearly two full wins below replacement level, courtesy of total breakdowns at bat, on the bases, and in the field. Of course, the Orioles wouldn’t make the playoffs even if they could replace their first-base flops with Prince Fielder the rest of the way; what we’re really interested in are the positional black holes that might actually pull a team out of the playoffs. With that in mind, here are this season’s 10 least-productive positions on contending teams to date, along with recommendations for how each club can try to fix its flaw from within.

Brewers, 3B (-1.8 WARP, .206 TAv, -2.1 FRAA)
Casey McGehee has been one of the worst players in baseball this season, but he’s received over 93 percent of Milwaukee’s innings at the hot corner. Fortunately, the Brewers have a potential solution in perennially-blocked prospect Mat Gamel, who played third almost exclusively before his defensive struggles spurred a move across the diamond this season. His minor-league mashing earned him a recent callup to serve as the team’s DH in AL parks, but Milwaukee should consider returning him to his original position and extending his stay beyond interleague play. The Brewers can’t afford to be complacent as they cling to first place in Prince Fielder’s walk year, and they might be better off with Gamel butchering balls at third as a starter or the long half of a platoon than they would be with more McGehee.

Rockies, 2B (-1.5 WARP, .225 TAv, -3.4 FRAA)
It takes an active imagination to see anything resembling a major-league regular in Jonathan Herrera, and only slightly less wishcasting to see something of real value in Chris Nelson or Eric Young. The Rockies would be better off handing the gig to Brad Emaus—who won an Opening Day job with the Mets before being cut loose after 42 plate appearances and going on to hit .313/.390/.569 for Colorado Springs—or playing Ty Wigginton at a position he’s less suited for than third.

Braves, 2B (-1.2 WARP, .211 TAv, 1.0 FRAA)
The Braves assumed second base would be a strength after acquiring Dan Uggla over the offseason, but while Uggla’s defense has been better than expected, his bat has been a no-show.  Though he hasn’t exhibited any signs of emerging from his offensive funk, the Braves have little choice but to stick with Uggla after signing him to a five-year extension in January that made him the highest-paid player at his position. Things would have to get even worse for Atlanta to consider replacing the owner of four consecutive 30-homer seasons with Brooks Conrad or further weakening an already-iffy outfield by moving Martin Prado back to the keystone.

Mariners, 3B (-0.9 WARP, .194 TAv, 0.2 FRAA)
Chone Figgins’ modest offensive outage in his first Seattle season has given way to a complete collapse at the plate in 2011. Much of his playing time has been bequeathed to Adam Kennedy, whose displacement from second base by Dustin Ackley immediately made him the M’s best option at third. The Mariners could also take a look at Alex Liddi, who has hit 14 homers for Triple-A Tacoma this season, but while the 22-year-old is young for his league, Liddi’s bat has barely cleared the PCL’s high bar, and his defense has never drawn rave reviews.

White Sox, LF (-0.7 WARP, .221 TAv, 1.3 FRAA)
Even in his prime, Juan Pierre wasn’t fit for a premium offensive position, so he makes little sense in left field in the midst of his worst offensive performance since his rookie season (.251/.311/.294 with a 52.6 percent stolen-base success rate). The Sox could replace him with 22-year-old Cuban Dayan Viciedo, who has hit .330/.369/.528 for Triple-A Charlotte while adapting to the outfield, and the versatile Brent Lillibridge, who could stand to get some additional looks in left.

Braves, RF (-0.6 WARP, .251 TAv, -2.6 FRAA)
Jason Heyward’s sophomore season has been no less injury-plagued than his rookie campaign, as the 21-year-old hit the DL in late May and missed nearly a month with lingering shoulder soreness that had tormented him since spring training. Even when Heyward was in the lineup, the injury prevented him from playing to his potential, though a motley crew of Matt Young, Joe Mather, and Eric Hinske hit even worse in his absence. If Heyward is now healthy, the Braves can forget about right field and devote their full attention to fretting about their investment in Uggla.

White Sox, 2B (-0.6 WARP, .228 TAv, 1.7 FRAA)
Last season, Gordon Beckham hit .216/.277/.304 in the first half but activated the afterburners after the All-Star break, boosting his batting line to .310/.380/.497. He’s been almost as bad in the first few months of this season, but the Sox should stand pat here and trust that the talented 24-year-old has another rebound in his bat.

Yankees, DH (-0.5 WARP, .254 TAv)
In the case of an established veteran off to a slow start, staying the course and waiting for an offensive renaissance can sometimes be a team’s best option. After appearing to be on his last legs in April and May, 39-year-old DH Jorge Posada has hit .393/.435/.589 in June, earning himself a longer leash. If he falters again, the Yankees can consider promoting top prospect Jesus Montero, whom some have suggested is bored by his extended stay in Triple-A.

Tigers, 3B (-0.5 WARP, .205 TAv, 6.0 FRAA)
Fantastic fielding by Brandon Inge has prevented this position from being an utter disaster, but the Tigers have yet to get any offense on the left side of their infield from anyone not named Jhonny Peralta. When Inge hit the DL after being diagnosed with mononucleosis earlier this month, he was replaced by Don Kelly, another glove-first player, and the other options in the mix—Ramon Santiago, Danny Worth, and off-season Triple-A import Argenis Diaz—are all made from the same good-field, no-hit mold. That’s a lot of leather and not much pop, but Inge managed league-average offense in each of the last two seasons, so Detroit’s best bet might be to wait and see if he can repeat the feat now that he’s feeling less fatigued.

Rockies, 3B (-0.4 WARP, .225 TAv, -3.2 FRAA)
Jose Lopez and Ian Stewart gave mile-high hot cornermen a bad name this season, but with Lopez in Florida and Stewart in Colorado Springs, the position is now nearly the sole province of Ty Wigginton, who’s brought some stability to what had been a festering wound on the Rockies’ roster. If Wigginton were to relocate to second to plug a hole there, Stewart could step in; the 26-year-old was a league-average player last season and has earned another shot by slugging .624 since his demotion.

Dan Turkenkopf and Rob McQuown provided research assistance for this story.

  A version of this story originally appeared on ESPN Insider Insider.