Per that report, he'll start for Single-A San Jose on Thursday and throw 70-75 pitches. He previously threw 3.2 innings for Triple-A Sacramento on Saturday, striking out eight without giving up a hit in 3.2 innings, according to the Associated Press.
That start was positive enough that Bumgarner said he would consider an immediate return to the Giants.
"I obviously didn't know before today, but judging off the way I felt out there, I think so, for sure," he said, per the AP. "I wouldn't say I'd be back and be in midseason form, but I feel definitely good enough to get some outs."
Bumgarner, 28, was sidelined by surgery on his pinkie in March after he injured it when he was hit by a line drive in San Francisco's final Spring Training contest. He appeared to have his full suite of pitches available to him in his first rehab appearance.
"I feel pretty good about how everything was working," he said. "My command was good. My breaking balls were doing pretty good also, so that's what I was looking for, everything headed in the right direction."
He continued: "The breaking stuff was moving right, the command of it was good. The fastball command was good. Pretty much everything I was looking for. It's not perfect, but it was definitely something to feel good about for the first time out there."
Getting Bumgarner back will be huge for a Giants team that has been up-and-down in 2018, opening the season 25-29. At the time of publication, the team's ERA was 4.55, 23rd in baseball, and the starting staff had provided 25 quality starts, 17th in MLB.
Bumgarner, meanwhile, has been one of baseball's top pitchers throughout his career. The four-time All-Star and three-time World Series champion had a disappointing season in 2017, however, going 4-9 with a 3.32 ERA, 1.09 WHIP and 101 strikeouts in 17 starts and 111 innings. A shoulder injury suffered while riding a dirt bike forced him to miss three months of the season.