GLENDALE, Ariz. -- National League Cy Young Award winner Clayton Kershaw is on schedule to make his Spring Training debut on March 9, despite having mild back tightness that pushed back his first bullpen session to at least Friday, manager Don Mattingly said Thursday.

"It's just precautionary. We're not taking a chance," Mattingly said of Kershaw's minor setback. "He's on schedule for his first start. The bullpen [session] is Friday, at least it's scheduled for Friday. He's able to do everything. He wanted to do the first bullpen [session Wednesday], but we're not letting him, just because he didn't want to miss the first day of school."

Kershaw felt tightness in workouts in the days leading up to the opening of camp this week. Named to start the spring opener, Kershaw lobbied to pitch, but was overruled by the medical staff.

Joining Kershaw on the precautionary list is reliever Mike MacDougal, who felt a twinge in his back during fielding drills on Wednesday and was scratched from his Thursday bullpen session. Mattingly said trainer Sue Falsone did not believe the injury was serious, and MacDougal, like Kershaw, was expected to participate in all other drills on Thursday.

The Dodgers also announced that non-roster invitee Jose Ascanio failed his physical. Ascanio, 26, missed the 2010 season with shoulder surgery and spent most of '11 at Triple-A. He had an eight-game callup with Pittsburgh, where he posted a 7.11 ERA.

Dodgers claim outfielder Angle off waivers

GLENDALE, Ariz. -- The Dodgers claimed speedy outfielder Matt Angle off waivers from the Orioles on Thursday and made room for him on the 40-man roster by placing injured pitcher Rubby De La Rosa on the 60-day disabled list.

Angle, 26, played 31 games for the Orioles last season, hitting .177 with one homer, seven RBIs and 11 stolen bases after spending most of the year at Triple-A Norfolk.

He's a 5-foot-10, 175-pound defensive specialist, a left-handed hitter and leadoff type who was a seventh-round Draft pick in 2007. Angle was designated for assignment by Baltimore.

Angle, who has two years of options remaining, gives the Dodgers some Triple-A outfield protection should they lose Trent Oeltjen, who is out of options and a longshot to make the 25-man roster.

De La Rosa is recovering nicely from Tommy John surgery in August, but he's not expected to be game ready until after the All-Star break at the earliest.