LAKE BUENA VISTA, Fla. — Braves reliever Jordan Walden has been nursing a sore left hamstring and hasn't pitched in a game since March 15.

But before anyone worries that it’s another injury that could linger for the hard-throwing setup man, he did some running Saturday and threw a side session in the bullpen Sunday morning without incident. He should pitch in a Grapefruit League game in the next day or two and be ready when the regular season begins March 31.

“I just threw a bullpen, and I’m good,” said Walden, who has made six relief appearances this spring and allowed six hits, three runs and two walks with five strikeouts in six innings.

“My leg just slipped a couple of days ago when I was extended,” the big right-hander said, demonstrating how his front leg went straight when his foot slipped while delivering a pitch.

Last spring in his first year with the Braves, Walden pitched in only five spring-training games and spent much of training camp getting treatment for a bulging disk.

He got an epidural and was ready when the 2013 season began. And after left-handers Jonny Venters and Eric O’Flaherty both had season-ending elbow injuries — Venters at the end of spring training, O’Flaherty six weeks into the season — Walden emerged as a top setup man for much of the season.

He had a 2.36 ERA and .203 opponents’ average in 37 appearances through July 29, with 39 strikeouts in 34-1/3 innings. But Walden struggled for the last two months of the season, posting a 6.39 ERA and .265 opponents’ average in 13 appearances after July 29 and missing three weeks with a strained groin beginning in late August.

In his only four September appearances after coming back from that injury, he gave up eight hits, six earned runs in 3-1/3 innings.

With Venters not expected back until June and O’Flaherty gone to Oakland as a free agent, the Braves’ top returning setup men are Walden, Luis Avilan (their only incumbent lefty) and David Carpenter.