Last season, it was a common point of view that Yuniesky Betancourt and the Brewers’ massive weakness at shortstop would be the doom for Milwaukee’s bid at competitiveness. As bad as Betancourt was, the real reason the Brewers needed a 22-3 stretch in August to overtake the St. Louis Cardinals for the National League Central crown was the struggles of Casey McGehee at third. McGehee put up an atrocious .223/.280/.346 line — a 68 wRC+ — and was eventually replaced by Jerry Hairston Jr. come the playoffs.

The Brewers moved earlier to fill their need at shortstop, signing Alex Gonzalez to a one-year deal with a vesting option. Today, the Brewers completed the left side of their 2012 infield, adding Aramis Ramirez on a three-year deal worth somewhere between $34 million and $37 million — that is, you the readers were pretty dang close.

Ramirez provides production from the plate the Brewers sorely missed at premium positions (other than second base) last season. The Brewers finished with a below-average position-adjusted OPS+ (sOPS+) at shortstop, center field, catcher and, of course, third base last season. Third base was the disaster — the other positions at least finished above 90. Thanks largely to McGehee, Brewers third basemen only produced 70% of the offense the rest of the league managed from the position.

Split BA OBP SLG OPS sOPS+ as LF .325 .392 .581 .973 165 as 1B .291 .407 .552 .960 140 as RF .278 .346 .485 .831 111 as DH .289 .289 .526 .816 109 as 2B .257 .335 .397 .732 107 as C .256 .306 .389 .696 98 as CF .265 .318 .396 .714 94 as SS .256 .277 .395 .672 91 as 3B .215 .275 .324 .598 70 View Original Table

Generated 12/12/2011. Provided by Baseball-Reference.com Generated 12/12/2011.

Ramirez promises to plug this offensive hole quite well. Even in his down year in 2010, when he limped to a .245 BABIP, he still finished with a 92 wRC+. Every other season since 2004, Ramirez has managed at least a 120 wRC+, making him one of the best hitters at the position over that period. Only Alex Rodriguez, Chipper Jones, David Wright, Evan Longoria, and Kevin Youkilis have better bats over the past eight seasons as measured by wRC+.

On defense, it will be more of the same for the Brewers — bad. Ramirez developed the nickname “E5” early in his career with the Pirates, and although he has since ceded that moniker to Edwin Encarnacion, little has changed with his ability. Ramirez ranks poorly no matter which defensive metric you look at, and he similarly fails the eye test. McGehee did grade out as a +7 UZR last season, but that was coming off two years of a combined -12. Having watched him quite often over the past three years, I must say I did not see too much different in 2011 from the rough sailing of 2009 and 2010.

Still, even with the defense factored in, Ramirez should be a major upgrade at third base, with his bat creating a potential 3.0-3.5 wins above replacement. Whether or not the Brewers “win” this deal will hinge on Ramirez’ health and longevity. With Ramirez turning 34 in 2012 and coming off an 89-game season in 2010, the deal could become a lemon as early as 2013, and Ramirez’ age-36 season in 2014 is a complete wild card. The Brewers appear more than willing to take that risk for the major short-term upgrade, however, and a 2012 replication of his 2011 season alone could validate the contract.