On Monday morning, Carlson indicated that he is currently nursing a sore left knee, which has kept him off a mound for much of the past week. The left-handed reliever is scheduled to throw a bullpen session on Wednesday, and he said Toronto's training staff is optimistic about his chances of being at full strength by Opening Day.
"They think it should be fine," said Carlson, pounding a fist into his glove as he stood at his locker in the Jays' clubhouse in Dunedin, Fla. "We'll see. Wednesday will be the big test."
Carlson said he felt some tightness in his knee early last week and indicated that the source of the issue is in the medial collateral ligament in the joint. He tried to pitch through the discomfort, working off a mound on Wednesday. Considering the problem is with Carlson's left leg, pushing off the mound during his delivery creates some pain.
Carlson alerted team trainers, and he was advised to rest the knee for a week before trying to throw off a mound again. In the meantime, Carlson has been able to play catch and do his regular workout routine.
"At first, I just thought it was soreness that would go away," Carlson said. "So I tried throwing on it. It was just agonizing, man."
With roughly three weeks remaining in Spring Training, the Blue Jays are not ready to rule Carlson out for Opening Day.
"Not yet," Blue Jays manager Cito Gaston said at Joker Marchant Stadium in Lakeland, Fla. "I guess if we find out that his knee is worse than what it seems to be, pretty much we would have to ... replace him. We do have someone to replace him, but we certainly haven't thought about doing that yet."
That said, Gaston said the bullpen picture now includes a new left-handed candidate.
On Monday morning, Gaston took in a "B" game against the Phillies at Dunedin Stadium, where lefty David Purcey struck out three over two shutout innings. Purcey entered the spring as a contender for the rotation, but is not currently among the front-runners for the starting staff.
In stints with the Blue Jays over the past two years, Purcey has gone 4-9 with a 5.81 ERA across 21 starts. Toronto pitching coach Bruce Walton has been working with the lefty on only throwing fastballs and sliders, abandoning his curveball and changeup for now.
So far, Gaston has been thrilled with the results.
"You would've been amazed with what you would've seen this morning," Gaston said. "He threw strikes. His arm slot was great. I think that we're probably leaning [toward making him a reliever] to see what he can do. We're just trying to find a slot for him that he's comfortable at.
"Hopefully, he continues to do that. I was very impressed. That's the best I've seen him throw since I've been here."
Even if Carlson is healthy, joining left-hander Scott Downs in the relief corps, Gaston said he might prefer to have three lefties in the bullpen. In the 27-year-old Purcey, the Jays potentially have a pitcher who could serve as a long reliever, which could prove important with such a young starting rotation.
"The one thing we're going to have to have this year is guys that can go more than one inning," Gaston said. "We've got a young pitching staff out there."
Gaston added that the Blue Jays have no plans of considering lefties Brian Tallet or Marc Rzepczynski for bullpen jobs. The manager said Tallet and Rzepczynski are secure in their roles as starters, even if Carlson is sidelined longer than expected. Lefty Brett Cecil is also in the mix as a candidate for the rotation, though he may wind up with Triple-A Las Vegas to open the season.
For Carlson, who pitched through pain for much of last season, the knee issue is a frustrating development. During the 2009 campaign, Carlson fought through a torn right pectoral muscle.
After fashioning a 2.70 ERA through his first 20 appearances last season, the 29-year-old posted a 5.48 ERA the rest of the way. Overall, Carlson went 1-6 with a 4.66 ERA in a career-high 73 games for the Blue Jays in 2009. It was a noticeable drop-off from his performance in '08, when Carlson had a 2.25 ERA over 69 games in his first tour with Toronto.
"It was hurting," Carlson said of the chest injury. "They mentioned the [disabled list] a bunch of times, but it was my right arm. I'm left-handed. That's why I kept going out there. I didn't want to go on the DL when it wasn't my throwing arm."
Once the season ended, Carlson was told to take a conservative approach to his offseason training program. The left-hander listened to the Blue Jays and did not begin throwing until January -- roughly a month later than he has started in previous winters.
As a result, Carlson does not necessarily feel like he is behind the rest of the pitchers, but he does not feel like he prepared as well as he would have liked to leading up to Spring Training. That adds another layer to his frustration, especially since Downs, Jason Frasor and Kevin Gregg are the only locks for the Opening Day bullpen.
Beyond Carlson and Purcey, the Blue Jays have a long list of arms in the mix for the four available relief roles. Other competitors include Casey Janssen, Jeremy Accardo, Shawn Camp, Josh Roenicke, Zach Jackson, Merkin Valdez, Zech Zinicola, Lance Broadway, Dana Eveland and Steven Register, among others.
Helping Carlson's case for a spot in the bullpen, if he is healthy, is the fact that he is left-handed and he has been a favorite of Gaston's. Toronto's skipper recently noted that pitchers such as Carlson and Camp might have an advantage because Gaston has had them in his bullpen in the past.
"Absolutely," Gaston said. "It helps, because I know what kind of people they are and what they're about. Certainly that helps them. That helps a lot."
Jordan Bastian is a reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.