Ryan Zimmerman's shoulder woes portend reconfiguration of Nationals' infield

Ryan Zimmerman's defense has been well below average at third base since 2010. (Alex Brandon/AP) Ryan Zimmerman once ranked among the game's best defenders,

Ryan Zimmerman's defense has been well below average at third base since 2010. (Alex Brandon/AP)

Ryan Zimmerman once ranked among the game's best defenders, but since the beginning of the 2012 season, problems with his right shoulder have turned his throws into adventures. In the wake of his being pulled from a game on Saturday, Nationals manager Matt Williams told a local radio station that the shoulder is arthritic and conceded that they're ramping up his work at first base, a move that could carry long-term ramifications for the team's infield.

Zimmerman emerged as a standout at the hot corner in 2007, his second full season in the majors; he ranked second only to Pedro Feliz in both Defensive Runs Saved (+18) and Ultimate Zone Rating (+16) that year, and from 2007 through 2010, ranked second only to Adrian Beltre in the former (+70 to +60) and Evan Longoria in the latter (+47 to +44). He's been 17 runs below average via UZR since, and after battling inflammation of his acromioclavicular (AC) joint during the 2012 season — necessitating multiple cortisone shots — he underwent a cleanup of his labrum and rotator cuff following the season. He has taken to throwing sidearm with some frequency since, but the results have been erratic. Last year's 16 throwing errors were four more than any other third baseman in the majors, though splits as to whether those came while throwing sidearm or overhand aren't available.

Fortunately for the Nats, the 29-year-old Zimmerman hasn't suffered at the plate. Last year, he hit .275/.344/.465 with 26 homers en route to a 121 OPS+, his same mark as the season before. Via Baseball-Reference.com's version of Wins Above Replacement (which uses DRS as its fielding component), he's been worth 3.9 and 3.8 WAR in the past two years, respectively — a handsome return for a player making $14 million a year. Via a six-year extension signed in February 2012, covering the 2014-19 seasons, he'll remain at that salary through the 2018 season; the salary climbs to $18 million in 2019 and 2020, the latter year a club option with a $2 million buyout.

Zimmerman has made two throwing errors in five games afield thus far this year, the second of which occurred during the fourth inning of Saturday's game, when he backhanded an Andrelton Simmons groundball and then tried to throw overhand but airmailed:

[mlbvideo id="31855601" width="600" height="336" /]

The error opened the door to a two-out, two-run rally, tying a game which the Nationals went on to lose. Zimmerman exited after the fifth inning and underwent an MRI that revealed inflammation but no structural damage, and thus no stint on the disabled list.

Williams expressed belief that the inflammation was caused by Zimmerman's throwing; he "plays catch constantly to keep him his arm loose, particularly in the early-season chill." Said the manager at the time:

“We look at it and say, it’s a little bit of overload,” Williams said. “We have to curtail that just a touch to make sure that he feels good. What does that involve? Maybe it doesn’t involve as many throws. Maybe it’s cutting down on the amount of grounders he takes in pregame. I know that he looks to go down, especially when it’s cold, in the cage and throw. Maybe it’s an adjustment to that, too.”

On Monday evening, Williams told radio station 106.7 The Fan that the team is giving Zimmerman some reps at first base:

“[T]he fact of the matter is, Ryan’s got an arthritic shoulder… It gives him problems, and sometimes it’s tough on him,” he said. “So we’ve started to do some things at first base, with him, where we can give him a break sometimes, in that regard, so he can go play first; he enjoys playing first; we did a little bit at spring training, worked hard at the position, and he enjoys it over there."

Time at first base for Zimmerman, who has never played the position in a regular-season game in either the majors or minors, would cut into the playing time of incumbent Adam LaRoche, who's signed through the remainder of this season for $12 million, with a $15 million mutual option and a $2 million buyout. LaRoche re-signed with the Nats after a big 2012 season, but he slumped to .237/.332/.403 with 20 homers last year, dropping 25 points of OPS+ (127 to 102) from the previous season. The lefty-swinger's woes against lefties (.198/.254/.313 in 142 PA) create a natural opening for Williams to shift Zimmerman to first base for a planned 10 to 20 games this year, but it's an option that the rookie manager has yet to use.

Assuming the Nationals part ways with LaRoche after the season, the team could shift Zimmerman to first base full time and move second baseman Anthony Rendon back to his natural spot; the sixth pick of the 2011 draft had played just eight minor league games at the keystone before being recalled last April. Those two moves in turn would allow the team to restore Danny Espinosa to full-time duty; the soon-to-be 27-year-old was limited to 44 major league games last season due to problems with his left (non-throwing) shoulder and a bone chip in his right wrist caused by a hit-by-pitch, and spent the second half of the year stashed at Triple-A. A .242/.319/.408 hitter with above-average defense in 2011-12 (his 2013 batting line isn't suitable for a family website) who also has the tools to play shortstop, Espinosa is coveted by other teams, who have attempted to pry him loose since he lost his job amid injury, but for the moment, he's limited to a utility role.

The Nationals have held onto Espinosa in part because he's so inexpensive; he's making just $540,850 this year and will be arbitration-eligible for the first time this winter. Swapping him into the lineup for LaRoche presents an opportunity for the team to cut costs, which appears to be on the mind of principal owner Mark Lerner, who last week described the team's $134.7 million Opening Day payroll — ninth in the majors and $25 million above 2013 — as "beyond topped out."

he'll play third