Four playoff contenders who could use upgrades at key positions

The Padres upgraded nearly every position on their team, but will third base be their Achilles' heel? They're one of four teams who need an upgrade at a key position.

As front offices scrambled this off-season to assemble postseason-caliber rosters, they were bound to miss a spot or two. More teams than ever enter the season with realistic aspirations for October, but most of their depth charts include holes that relegate them to the playoff fringe and starters who offer little upside or security. Here are the positional weaknesses that could most easily derail these contenders’ playoff hopes.

Blue Jays: Justin Smoak, 1B

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The Blue Jays, in a go-for-broke season, have conferred first base to Smoak in hopes that he’ll redeem the erstwhile top-prospect label that once made him the key piece the Mariners obtained in exchange for Cliff Lee. But over 2,000 career plate appearances, Smoak has proven to be essentially valueless. The first-baseman was terrible in 2014, hitting .202 with a .614 OPS and providing no base-running or defensive value. Both Fangraphs (-0.4) and Baseball-Reference (-0.6) pegged Smoak as below replacement level for the season. Smoak has been better through the early part of '15, with a .368 on-base percentage in 19 plate appearances. But with just one extra-base hit so far, he's not showing the power Toronto needs from a corner position.

As for the Jays' alternatives to Smoak, Toronto can turn only to Edwin Encarnacion, who was brutal defensively in 80 games at first last year, and backup catcher Dioner Navarro. In what might be the aging Blue Jays’ last chance at the playoffs in the near future, they could use an external upgrade at first base.

Padres: Will Middlebrooks/Yangervis Solarte, 3B

After an off-season spending spree that strengthened their outfield, rotation and bullpen, the Padres find themselves bone dry at third base, where they’ll rely on AL East outcasts Solarte and Middlebrooks.

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​Solarte and Middlebrooks are 27 and 26 years old, respectively, without a full big league season between them. Middlebrooks flashed promise with the Red Sox in 2012, posting 15 homers, a 121 OPS+ and 1.3 WAR in 75 games. But a broken wrist cut short his season, and his '13 suffered for it, as he struck out nearly five times for every walk and managed just an 87 OPS+. He was even worse in '14, slumping to a .522 OPS (and again missing time with injuries) before being traded in the off-season. Solarte, meanwhile, was red-hot early on for the Yankees in his rookie year, with an .865 OPS through the first month of the season. But he slowed down significantly after that, cratering in June with a .164/.282/.213 line, then getting sent to the Padres in a midseason deal for Chase Headley.

Solarte is once again off to a fast start, with eight hits in his first 22 at-bats of 2015, while Middlebrooks has struggled, with more strikeouts (11) than hits (nine) so far. But as last year showed, the Padres can't count on Solarte to produce over a full season, and Middlebrooks's lack of plate discipline was his biggest issue in Boston. Neither, meanwhile, has looked anything more than average defensively (albeit in small sample sizes for both).

Beyond those two, San Diego's options include Clint Barmes, Cory Spangenberg and the waiver wire—in other words, not much. And with offensively challenged Alexi Amarista at shortstop, San Diego must overcome or improve upon major holes on the left side of the infield in order to sniff the playoffs.

Cubs: Chris Coghlan, LF

The Cubs have an impressive amount of top prospects available to fill some of their notable holes, but with Kris Bryant playing exclusively third base at Triple A, there’s no outfield cavalry riding up from the minors any time soon. That leaves Chicago to pray that incumbent Coghlan’s solid 2014 and torrid start to '15 (.304 average and .696 slugging percentage through eight games) indicate a sustainable improvement upon his previous self. But if Coghlan reverts to his '13 form—an 85 OPS+ and just one homer in 70 games—leftfield will pose a major problem for the playoff-hopeful Cubs.

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The Cubs’ best bet is to platoon the lefty-hitting Coghlan with righty Chris Denorfia, once the latter returns from the disabled list. But even if Chicago maximizes the two players’ abilities, the position will remain a weak spot. Coghlan's 2014 was his first above-average season since '09, so regression should be expected. Denorfia, meanwhile, was dependable at the plate from '10 to '13 but fell off last season, managing just a .602 OPS split between the Padres and the Mariners. At age 34, Denorfia could be solidly in the downturn of his career. And neither carries much of a reputation in the field.

Yankees: Stephen Drew, 2B

When Robinson Cano left the Bronx before the 2014 season, he left behind a massive void, which the Yankees have plugged with a slew of overmatched fill-ins. This offseason, Brian Cashman traded his one dependable second-base option, Martin Prado, leaving the position to Drew, Jose Pirela, Rob Refsnyder and recently Gregorio Petit.

Drew, who had never played second until last season, posted a ghastly 44 wRC+ in 2014 and got off to a comparably bad start this year, batting .148/.200/.370 so far, and has hit just .243/.319/.405 since '10. Drew’s struggles over the last year leave the Yankees looking toward the future, but youngsters Refsnyder and Pirela won’t fix the position immediately. Pirela is currently on the disabled list with a concussion, and Refsnyder has a .541 OPS at Triple A, as well as three errors in just six games.