Dodgers closer Kenley Jansen will start the season on the disabled list as he recovers from a foot operation he underwent Tuesday. Jansen is expected to be sidelined for eight to 12 weeks, meaning he could miss as many as the first five weeks of the regular season.
Jansen's surgery came only two days before the Dodgers' pitchers and catchers report to the team's spring-training complex in Arizona.
The unexpected development could present problems for the Dodgers, who spent their off-season rebuilding a bullpen that was considered a major weakness last year. By the time the Dodgers were facing the St. Louis Cardinals in a National League division series, Jansen was considered the team's only reliable reliever.
Jansen, 27, saved a career-high 44 games. He posted a 2.76 earned-run average and struck out an average of 13.9 batters per nine innings.
With Jansen expected to be on the disabled list for relatively short period, the Dodgers aren't expected to make a serious push for either Francisco Rodriguez or Rafael Soriano, the top two relievers still on the free-agent market. A trade for Jonathan Papelbon of the Philadelphia Phillies is also believed to be unlikely.
News of problems with Jansen's left foot came suddenly, according to the Dodgers. Jansen reported discomfort while running last week, the team said in a written statement.
Jansen subsequently underwent a series of exams, which revealed a growth from the fifth metatarsal in his left foot. The growth was removed Tuesday morning in an operation performed by Drs. Earl Brien and David Thordarson, who worked under the direction of team physician Dr. Neal ElAttrache.
Jansen will be on crutches for 10 days, after which he will be in a boot for three to four weeks.
Jansen's temporary replacement probably will come from a bullpen that was reconstructed over the winter by the team's new front office. The bullpen might be improved, but doesn't include any obvious candidates to step into the ninth-inning role.
The Dodgers released ineffective setup man Brian Wilson, even though they are obligated to pay him $9.5 million this season. They also made no effort to re-sign Chris Perez, another former All-Star closer.
Liberatore will compete with the likes of Paco Rodriguez, Daniel Coulombe and non-roster pitcher David Huff to be the second left-hander in the bullpen alongside J.P. Howell.
Closer-turned-middle-reliever Brandon League will return this season for the final guaranteed year of his three-year, $22.5-million contract. Hard throwers Pedro Baez and Yimi Garcia are also back.
Of the non-roster pitchers who will be in camp, David Aardsma and Sergio Santos have experience closing. Aardsma saved 38 games for the Seattle Mariners in 2009, while Santos saved 30 games for the Chicago White Sox in 2011.
The front office is optimistic this group will walk fewer batters than last year's, which averaged 3.79 walks per nine innings, fourth-worse in the majors. The Dodgers posted a bullpen ERA of 3.80 that ranked 22nd in the majors and was worst among the five National League playoff teams.
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