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08/29/12 8:08 PM ET

Recurrence of heart condition sidelines Jansen

Dodgers closer missed four weeks last season with similar episode

DENVER -- After his club hung on to a wild 10-8 win over the Rockies on Wednesday to snap a three-game losing streak, manager Don Mattingly revealed that closer Kenley Jansen is out indefinitely with a recurrence of an irregular heartbeat that sent him to a local hospital before Tuesday night's game.

That's why Ronald Belisario was pressed into a five-out save of a game the Dodgers led by nine runs in the eighth inning.

But the win was overshadowed by what the Dodgers now must overcome.

Earlier Wednesday, lefty reliever Scott Elbert was placed on the disabled list with a sore elbow that likely will require surgery. And all of a sudden, the knee contusion that outfielder Matt Kemp suffered slamming into the fence Tuesday night didn't seem so critical.

"We'll keep moving forward," said Mattingly, who can't wait for rosters to expand Saturday and the arrival of relievers Matt Guerrier and Javy Guerra, among others.

Mattingly, however, doesn't know for sure when Kemp will return to the lineup and if he knows much about Jansen's prognosis, he wasn't saying. The reliever, released after being hospitalized overnight, was not in the clubhouse when reporters arrived and he did not give the club permission to discuss his condition.

What is known is that he missed four weeks last year with a similar episode that required blood thinners, which forced him to go on the disabled list because of the bleeding risk in baseball activities. He also had a mild episode during Spring Training this year but did not miss playing time.

There are other possible treatments, but if the blood thinners are required, Jansen is probably out for the rest of the year. He has 25 saves and a 2.54 ERA, having inherited the closer job from Guerra in April.

Jansen pitched Monday night in the high altitude and was battered for four runs in two-thirds of an inning.

Ken Gurnick is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.