NEW YORK -- The Blue Jays initially believed that Shaun Marcum might be ready to rejoin their rotation by now. The club's latest stance is that it probably makes more sense to let him finish out the season in the Minor Leagues.

"We're leaning more toward that, probably, at this point," general manager J.P. Ricciardi said.

Marcum, who underwent Tommy John ligament-replacement surgery on his right elbow last September, is with Triple-A Las Vegas. He tweaked his back toward the end of July, setting him back and leading Toronto to reconsider its plans to bring him back to the big leagues so soon.

Marcum last pitched for Vegas on July 26 and has made five rehab starts between Class A Dunedin, Double-A New Hampshire and Triple-A, posting a 2.30 ERA over 15 2/3 innings. He is going to miss some time on the hill this month given that his wife is due to give birth to their second child -- another reason not to unnecessarily rush him to Toronto.

"He's healthy," Ricciardi said. "There's nothing wrong with him, but there's no reason to rush him. He's going to pitch next year for us. He'll be like 17 months post-op at that time. He feels good. We'll probably just keep throwing him, but there's really probably no need to get him to the big leagues at this point.

"We'll just back off that way and give him all of Spring Training to simulate the intensity of what it is to pitch in a big league game."

The same goes for right-hander Casey Janssen, who underwent surgery on his right shoulder in March 2008 and has experienced a few setbacks this season. Janssen is pitching for Las Vegas as a reliever, and Ricciardi said that he will enter the Jays' bullpen when he does return. As with Marcum, that might not be until next season.

"Eventually, he'll be back up here, but he just needed to pitch," Ricciardi said. "Maybe this year is just going to be a year where all the kids get healthy and, at the end of the day, we check off September and we say, 'They're healthy. They feel good and, coming into Spring Training, we're not worried about Casey's arm and we're not worried about Marcum's arm.' "