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06/27/12 2:25 PM ET

No timetable on Santos' return to bullpen

BOSTON -- The mysterious case of Sergio Santos' injured right shoulder continues without any sign of it coming to an end any time soon.

Santos has been on the disabled list with inflammation in his shoulder since April 21. He was originally expected to be out for only two to four weeks, but more than two months have passed and he still hasn't experienced any improvement.

Toronto's Opening Day closer has started throwing and stopped on at least a couple of occasions and has been unable to take part in loss toss because of the lingering soreness.

"It has been frustrating for him, because as he has increased the intensity, got back to the mound, had the setback," manager John Farrell said. "I think if you ask any athlete when they have a setback because of an injury, it's frustrating. Then you follow up with further evaluation, the images that take place to get further information.

"We're all hopeful that there's not another setback, because at that point then we've got to really re-assess what the next step is."

Perhaps the most bizarre aspect of Santos' injury woes is that the pain hasn't been restricted to one area of the shoulder.

"He has experienced discomfort on the front side, he has experienced it on the back side," Farrell said. "It has moved around at times and that's -- without speaking directly for Sergio -- I think where some of the frustration lies, because it's not always in one same spot."

Santos appeared in just six games for the Blue Jays this season before going on the DL. Last year with the White Sox, Santos was 4-5 with 30 saves and a 3.55 ERA in 63 1/3 innings.

Villanueva prepared for rigors of starting

BOSTON -- Carlos Villanueva is set to become the 10th different starting pitcher used by the Blue Jays this season when he takes the mound on Friday night against the Angels.

Villanueva, who has spent the entire year pitching in long relief, was promoted to the rotation following a pair of inconsistent outings by right-hander Jesse Chavez.

A starting role is nothing new for Villanueva, as the Dominican native has made 40 career starts, including 13 with the Blue Jays last season.

"I was always a starter and I like to be in control of things, so when I'm starting, I'm in control from the first pitch of the game," Villanueva said of his desire to start. "If you're going to ask me selfishly, of course, but I'm not a selfish person. If they want me to do whatever, I'll do it. I'm getting an opportunity to help the guys out in this role and I'll do the best I can."

This is the second consecutive year that Villanueva has been pressed into starting duties. Last season, he replaced an injured Jesse Litsch and proceeded to make 13 starts.

The first nine outings went extremely well, as he posted a 4-1 record with a 3.67 ERA. The final four didn't go nearly as smoothly, in part because of a lingering right forearm injury that eventually forced Villanueva onto the disabled list.

In those last four starts, Villanueva went 1-3 with a 9.31 ERA. He feels this year he is much more prepared to handle the rigors of taking the mound every fifth day for an extended outing.

"The season prior I prepared to throw 60 or 70 innings out of the 'pen," said Villanueva, who lost more than 30 pounds during the offseason. "Even my friends asked me, 'What if you start?' And [I] was like, 'Yeah, I got no chance.' But this year with what happened last year, I just didn't take any chances.

"I came in a little better shape this year and maintaining all year a little more vigorous workout routine, so that should help me physically at least. It won't come as a surprise to my body."

Manager John Farrell said that Villanueva should be able to throw approximately 75-85 pitches in his first start. Villanueva will be gradually stretched out over time, and Farrell added that he is now in the rotation to stay.

Toronto's starting rotation has been decimated by injuries in recent weeks. Right-handers Brandon Morrow, Kyle Drabek and Drew Hutchison are currently on the 15-day disabled list, while Henderson Alvarez was forced to depart Monday's outing with right elbow soreness.

Morrow starts throwing, hopes to avoid setback

BOSTON -- Brandon Morrow has resumed throwing approximately two weeks after being forced to depart his start against the Nationals because of a strained left oblique.

Morrow began having a light catch on Monday. He is expected to throw every other day, but there is still no timetable for his return.

"If there was pain, we wouldn't throw him," manager John Farrell said. "The symptoms are continuing to subside. Now we've got to gradually increase the intensity. That will be a slow process, not, you know, risk any kind of setback."

Morrow was enjoying a breakout season prior to the unfortunate injury. He is 7-4 with a 3.01 ERA while also recording three shutouts in 13 starts.

The 27-year-old is currently working out at the club's Minor League complex in Dunedin, Fla. He isn't expected to be ready for a return to the Majors until at least late July.

"It's more just getting his arm moving again," Farrell said. "Naturally there's going to be a little rotation involved there with the throwing motion, but we're not overloading it by any means."

Chris Toman is an associate reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.