"He's coming along, he's got a cast or splint on there, but I know he's excited to get those things out," Giants manager Bruce Bochy told reporters Thursday.
The 28-year-old lefty was injured March 23 when he was hit bya line drive off the bat of Kansas City's Whit Merrifield in a spring training outing.
Bochy remains optimistic that Bumgarner will be able to return to rotation in June. The 2014 World Series MVP is eligible to come off the 60-day disabled list on May 25.
"Knowing him, how hard he's going to work," Bochy said. "It all depends when he starts throwing. He's a ways away, probably two weeks before you start playing catch."
Bumgarner had a 3.43 ERA with 30 strikeouts in 21 innings this spring.
San Francisco has yet to win a series this season.