The 25-year-old center fielder joined the Yankees for their trip to Baltimore and went through light flip-hitting drills on Monday at Camden Yards. He will take batting practice on Tuesday, and he believes that his thumb is close to fully healed.
"I really didn't have much discomfort," Gardner said. "I could feel it a little bit, but I was under the assumption that if I felt anything, I'd just shut it down and be careful. It's felt better every day."
Gardner has been sidelined since a play at Yankee Stadium on July 25, when he slid into Athletics second baseman Mark Ellis and reached out to touch the base with his left hand. The thumb dragged over the base and caught awkwardly; the fracture was revealed after the game.
Gardner believes that he will be dispatched to play for Triple-A Scranton/Wilkes-Barre on Thursday, when the Yankees travel north of the border to open a four-game series with the Blue Jays.
"Any time you can see some live pitching and swing the bat a little bit, get some at-bats, it definitely helps," he said.
Manager Joe Girardi is looking forward to mixing Gardner back into the outfield rotation, but the impression is that Gardner -- who was the Opening Day starter -- is to serve as a backup to Melky Cabrera.
Utilityman Jerry Hairston Jr. would fall to third on the depth chart once Gardner returns from the rehab assignment.
"I think a lot of it just depends on how he's feeling and how his at-bats are," Girardi said. "He hasn't played in a while, and you want to make sure his legs are under him, because that's a big part of his game."
Though the Yankees will not have Gardner ready to go on Tuesday, when rosters expand to 40 players, Girardi did hint that the club would call up more than two pitchers as well as multiple position players, with Francisco Cervelli and Ramiro Pena likely candidates.
Bryan Hoch is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.