© 2013 MLB Advanced Media, L.P. All rights reserved.

8/13/2013 8:46 P.M. ET

Perez passes on Tommy John, will rehab elbow injury

TORONTO -- Blue Jays left-handed reliever Juan Perez has opted not to undergo Tommy John surgery and will instead attempt to rehab his left elbow injury.

The veteran reliever suffered a partially torn ulnar collateral ligament during an outing against Oakland on Aug. 9. The belief was that he would require surgery, but he's opted for rest and will see how the ligament responds in approximately eight weeks.

The decision does make some sense considering Perez will turn 35 in September and Tommy John surgery would likely keep him out all of next season. That would put his career in serious jeopardy, but if he can avoid the procedure, it would give Perez an opportunity to possibly compete for a job next spring.

Perez was a journeyman pitcher who appeared in parts of four seasons in the big leagues before finding a home in Toronto. He responded by posting a 3.69 ERA in 31 2/3 innings.

Johnson headed to DL, may be done for season

TORONTO -- Josh Johnson's disappointing 2013 season took another hit on Tuesday afternoon when it was announced the Blue Jays right-hander is headed to the disabled list because of a sore right forearm.

The move won't become official until Wednesday, but Johnson will be placed on the 15-day DL while right-hander Thad Weber is being recalled from Triple-A Buffalo.

Johnson will undergo an MRI to determine the exact nature of his injury, but he has been at least temporarily shut down and there is no timetable for his return.

"Doctors are just taking a look at him now and they're going to send him for MRIs," general manager Alex Anthopoulos said early Tuesday evening. "Off the exams, structurally and things like that, it doesn't look serious, but he doesn't feel right."

Johnson first experienced the discomfort during his last start against the Mariners on Aug. 6. His scheduled outing Sunday was then pushed back a couple of days to provide some additional rest, and for awhile, it appeared as though everything was going to be fine.

That changed prior to Tuesday night's game against Red Sox. Johnson played catch and felt his forearm tighten up to the point where he believed it wouldn't be smart to continue throwing.

The injury couldn't have come at a worse time for Johnson, who went through weeks of struggles on the mound before finally figuring things out against Seattle. Johnson pitched five scoreless innings against the Mariners and had plenty of positives to take away from the outing, but none of that seems to matter now.

"Before the last start, that was the best I felt in three years," Johnson said. "Shoulder, elbow, everything felt right where it needed to be. I don't know what happened, but I came out of that start and I was a little sore and tight."

Even if the MRI results don't reveal any structural damage, Johnson will be hard-pressed to return before the end of the season. With only six weeks left in the season, Johnson would need to quickly recover and then at least pitch in a couple of simulated games before rejoining his teammates in Toronto.

Johnson said he felt the discomfort feels more related to a muscle than a ligament in his elbow. That's an encouraging sign and there will be plenty of incentives for the soon-to-be free agent to return for a start or two in September, but it will be a tough task to accomplish.

"That's the only thing I want to do is be on the mound," Johnson said. "Especially after how I felt in the last bullpen in the last game. That's the one thing I want to do, is get back out there, but this is holding me back for sure."

Johnson was acquired as one of the major components in a blockbuster trade with Miami during the offseason. His season was sidetracked early on with a right triceps injury and he wasn't able to get things figured out. The 29-year-old is 2-8 with a 6.20 ERA in his 16 starts this year.

Rasmus may land on DL with injured oblique

TORONTO -- Colby Rasmus is in danger of requiring a stint on the 15-day disabled list if his injured oblique muscle doesn't improve soon.

Toronto's center fielder missed his second consecutive game Tuesday night and is being held out of all baseball activities. The real test will come Wednesday morning, but if he's not healthy enough to hit in a cage then he'll likely require an extended period of time off.

Rasmus suffered the injury while checking his swing during an at-bat against Oakland's A.J. Griffin on Saturday. Rasmus has dealt with oblique injuries before, so he knows all too well how they can linger without appropriate rest and treatment.

"I've had oblique injuries throughout playing and it's nothing to play with," Rasmus said. "There were times when I played through it and it wasn't the best thing for me and the ballclub. So this time I'm just going to make sure I do right and minimize the time."

The loss of Rasmus would be another serious blow to the Blue Jays. especially considering he has become one of the club's best hitters in recent months.

Since the beginning of July, Rasmus is hitting .331 with four homers, 14 doubles and 22 RBIs while posting an .899 OPS over 36 games. It's one of the best stretches of his career and he remains one of Toronto's only position players to have exceeded expectations this year.

Rasmus was hoping to resume baseball activities Tuesday, but when he woke up and felt a sharp pain while sneezing it became apparent that wouldn't be the case. There isn't much that can be done besides rest, which makes it all the more likely he'll be forced to hit the DL in the coming days.

"I don't have a magic equation for it," Rasmus said. "I'm just going to try and feel it out and take my time with it. If it keeps bothering me, then I'm going to shut it down."

The Blue Jays have a couple of options at their disposal to replace Rasmus, but the early favorite likely is outfield prospect Kevin Pillar.

Pillar is hitting .303 with four homers and 27 RBIs in 51 games for Triple-A Buffalo. He would likely start in left with Rajai Davis and Emilio Bonifacio splitting time in center field.

Another candidate is outfielder Anthony Gose, but the 23-year-old has fallen down the organization's depth chart amidst a disappointing season in Buffalo. Gose is hitting just .237 with an alarming 118 strikeouts in 384 at-bats for the Bisons.

Gregor Chisholm is a reporter for MLB.com. Read his blog, North of the Border, and follow him on Twitter @gregorMLB. This story was not subject to the approval of Major League Baseball or its clubs.