In 2012 -- not so much. Walden lost his closer job to Ernesto Frieri, and stumbled through the first half of the season, posting a 3.86 ERA and 1.571 WHIP in 31 appearances; he has just one save this year. And now, he's going to sit for at least 15 days:
The move, according to this tweet from Victor Rojas, is retroactive to July 9, so Walden will be eligible to come off the disabled list ten days from now. It's probably designed more to give him some rest, more than for any injury that's serious.