Nationals manager Davey Johnson said Storen's elbow felt tender after the right-hander threw a simulated game Sunday at the team's spring training complex in Viera, Fla. Storen, who saved 43 games last year in his first full major league season, is on the 15-day disabled list and Washington had hoped he would be able to return this month.
"We had a little bit of bad news on Storen," Johnson said Monday before the Nationals opened a three-game series against the New York Mets. "Hopefully it's nothing serious, but it doesn't sound good to me."
Johnson also revealed that doctors thought they may have noticed a loose body in Storen's elbow during an earlier test this spring, but they weren't positive. He said it doesn't seem as though rest and treatment alone are fixing the problem.
Storen was one of baseball's best closers last season, going 6-3 with a 2.75 ERA and 43 saves in 48 chances. He appeared in 73 games.
The 24-year-old reliever was selected 10th overall in the 2009 amateur draft out of Stanford.
Washington added some insurance at the back end of the bullpen when it signed Brad Lidge in the offseason to a $1 million, one-year contract. The 35-year-old Lidge, an All-Star closer in Houston and Philadelphia, saved a 2-1 win over the Chicago Cubs on opening day.
The group of relievers, which also features All-Star setup man Tyler Clippard, was a strength for the Nationals last season and Johnson said he thinks his team has enough depth to overcome Storen's absence.
In other news, Johnson said left fielder-first baseman Michael Morse should be back for the team's home opener Thursday against Cincinnati. Morse is rehabbing a back injury at Double-A Harrisburg and Johnson said he saw no reason to rush the slugger back for this series against the Mets.
Morse batted .303 with 31 homers and 95 RBIs last season. He is eligible to come off the disabled list Tuesday.