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2/17/2013 5:20 P.M. ET

Reliever Withrow sidelined after back spasms

GLENDALE, Ariz. -- Chris Withrow said he expects to be sidelined a few days with back spasms he experienced during his Friday bullpen session.

Withrow has had two previous episodes with a bulging disk that have sidelined him for extended periods, but he said the current discomfort is less than those and an MRI showed that the disk hasn't been further compromised.

"I don't think I made the existing injury worse," said Withrow, the club's 2007 first-round Draft pick, who is making a transition from starting pitcher to reliever.

Withrow, who with his wife survived an offseason rollover auto accident with only minor injuries, said this is the first time he's been injured while pitching. His earlier episodes were triggered by conditioning exercises and weight lifting.

"This is new for me, which is why I think it's not as bad," he said. "I'll take it easy a couple of days and make sure it doesn't flare up."

Crawford feels good after first batting practice

GLENDALE, Ariz. -- Carl Crawford took his first live batting practice session on Sunday and it must have been a big deal because it was observed by manager Don Mattingly, general manager Ned Colletti, president Stan Kasten and assorted other front-office execs.

Crawford has been hitting in the cage, but this was his first regular batting practice since undergoing Tommy John surgery on his left elbow last August. His hitting group included Matt Kemp, Hanley Ramirez and Andre Ethier.

"I was really surprised," said Mattingly. "For the first time in open space, that's just a lot different, and I'm sure he doesn't feel good, but I thought he was good."

Actually, Crawford wasn't complaining.

"For the first day, didn't feel too bad," said the left fielder. "Maybe it was the group of hitters, but it went better than I expected. It feels normal hitting."

Throwing will be the final hurdle and Crawford remains on a conservative program designed to build arm strength.

"Still going slow there," he said. "I have good days and bad days throwing. That part is still a little shaky. But I'm throwing on my program every other day and make 20 throws on the days in between to stay loose."

Jansen has bullpen session after toe injury

GLENDALE, Ariz. -- Dodgers reliever Kenley Jansen, who will have a painful ingrown toenail removed on Monday, was able to make his regular bullpen session on Sunday without limitations.

Jansen, who missed part of Saturday's workout because of the discomfort, was also able to take part in pitchers fielding practice.

Jansen, expected to fill a set-up role to closer Brandon League, is returning from surgery to correct an irregular heartbeat.

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