TORONTO -- Blue Jays manager John Farrell is expected to be away from his team until at least Friday because of pneumonia.

Farrell was taken to the hospital on Thursday night after experiencing discomfort in the left side of his chest. He was diagnosed with pneumonia and has been away from the team since.

"Still feeling a little shaky, so we made the decision that he will not be with us in the Baltimore series," Blue Jays acting manager Don Wakamatsu said. "We'll evaluate him and see when he'll be able to return at that point once we're on the road."

Farrell arrived at Rogers Centre on Monday afternoon to be examined by the club's medical staff. He is improving, but hasn't reached the point where he has been cleared to make a return.

General manager Alex Anthopoulos met with the first-year manager after he was examined and the decision was made for Farrell not to make the trip on Monday night to prepare for a three-game series in Baltimore.

The club remains optimistic that Farrell will join the team in New York on Friday, but it's still too early to know for sure.

"I think he came in today thinking he was going to try to manage but he's still a little weak," Wakamatsu said. "Just to be safe, this is not something you want to play around with obviously and just make sure [we] get him back on his feet."

It was initially believed that Farrell would be out of action for only a couple of games. Despite the recovery not progressing as quickly as Farrell initially hoped, the Blue Jays said there isn't anything severe taking place.

"I think it's one of those things where you just don't know," Wakamatsu said. "Obviously with pneumonia you got to be awfully careful, but he felt good enough to come in today to make sure he gets checked out and we just want to be safe with it."

Rauch, Villanueva working way back to roster

TORONTO -- Blue Jays right-hander Jon Rauch threw his second bullpen session on Sunday afternoon and could be activated from the 15-day disabled list late this week.

Rauch has been out since undergoing an appendectomy in Seattle on Aug. 16. He was expected to be out three to four weeks, but appears to be ahead of schedule and will not require a rehab assignment.

"The plan is right now for him to throw a simulated game, possibly [Tuesday]," Toronto acting manager Don Wakamatsu said. "Maybe do some fielding practice and look at maybe Thursday activating if everything does well."

Right-hander Carlos Villanueva is also in the process of working his way back to Toronto. Villanueva, who is on the 15-day disabled list with a right forearm strain, threw 15 pitches in his first rehab appearance for Class A Dunedin on Sunday afternoon.

The Dominican native allowed one hit and unearned run during his inning of work. He will pitch again on Wednesday, but the club is unsure whether it will be for one or two innings.

Villanueva is 6-3 with a 4.24 ERA in 26 games this year. He is eligible for arbitration at the end of the season.

Tallet returns from rib-cage strain

TORONTO -- The Blue Jays activated left-hander Brian Tallet off the 15-day disabled list on Monday afternoon.

Tallet hasn't pitched in the Majors since suffering an intercostal strain in his rib-cage area on July 3. The veteran reliever had his flight to Toronto delayed on Monday, but arrived just before Toronto's series finale against the Rays.

The 33-year-old lefty has yet to pitch for the Blue Jays this season. He was acquired along with Colby Rasmus in a multiplayer deal on July 27 and immediately began rehabbing the injury at the club's Minor League Complex in Dunedin, Fla.

Tallet made four appearances for Class A Dunedin and allowed one run in four innings. He also surrendered four hits and struck out five without issuing a walk.

The Oklahoma native previously spent five seasons in Toronto. He is 16-24 with a 4.76 ERA in 241 career appearances.

Toronto opened a spot on its 25-man active roster on Sunday when left-handed reliever Wil Ledezma was designated for assignment.