NEW YORK -- Right-hander Jason Hammel had an impressive first rehab start, but manager Buck Showalter said the team will probably wait until his bullpen session before determining if Hammel is ready to come off the disabled list.

Hammel tossed five scoreless innings for Class A Advanced Frederick on Saturday night, striking out seven and allowing three hits and a walk with executive vice president of baseball operations Dan Duquette in attendance. The righty, who turned 30 on Sunday, is expected to join the team in New York on Sunday afternoon and will fly to Toronto and throw a bullpen session under the watchful eye of pitching coach Rick Adair.

"I want to talk to Ham and get a little more detail from Dan and see where he fits," Showalter said of Hammel, who would line up to pitch Thursday's game versus the Yankees if deemed ready. "But that was real encouraging last night. That was about as good as you can expect."

Hammel has been sidelined since mid-July after undergoing arthroscopic surgery on his right knee, and his return would help add some stability to an Orioles rotation that has been piecing it together day by day. Newly acquired Joe Saunders will start Monday's game in Toronto, with Zach Britton in line to start Tuesday after Triple-A Norfolk's season ends. The rest is still to be decided.

"It'd be great to get Ham healthy and pitching and we can actually give you a rotation two series in advance," Showalter said.

Hunter expected to join O's bullpen in Toronto

NEW YORK -- Pitcher Tommy Hunter will join the Orioles in Toronto and is expected to be called up from Double-A Bowie before Monday afternoon's game, which would make it 10 days since being optioned.

Hunter, who tossed a scoreless inning for the Baysox on Friday night, will be used out of the bullpen.

"He was 96 [on the radar gun] yesterday closing," manager Buck Showalter said of Hunter, who has appeared in three games in relief for the Orioles this season. Hunter has gone 4-8 with a 5.71 ERA in 20 starts in 2012, and he's pitched 4 1/3 innings in relief, allowing six earned runs on 10 hits and two walks, with four strikeouts.

"Tommy's pitched some big games for us starting this year," Showalter said. "Some people would think he would be a good fit in the bullpen, too."

Hunter has 13 career relief outings, going 1-1 with a 5.06 ERA. Over 21 1/3 relief innings, the 26-year-old has allowed 24 hits, 13 runs (12 earned), seven walks and three home runs. He has struck out 15.