Before the Jays' Wednesday night tilt with the Reds, Ricciardi updated the status of several of the club's injured starting pitchers. The GM said there still is no timeline for McGowan's return.
McGowan underwent surgery to repair a frayed labrum in his right shoulder last May, and his recovery has stalled recently.
"Dustin is slow. He's been a slower process," Ricciardi said. "I don't know when he'll come back."
When asked if McGowan would ever pitch in the Major Leagues again, Ricciardi could not give a definite answer.
"I don't know if he's never going to throw again, but right now, he's struggling. He's not where he should be from a rehab standpoint."
McGowan began throwing again in late May, but he has not made much progress from that point.
"He's playing catch," Ricciardi said. "He can't get beyond playing catch right now."
The outlook was far more optimistic for Marcum, who underwent Tommy John elbow ligament replacement surgery in September 2008. He threw his first simulated game since the surgery on Wednesday, pitching two innings, Ricciardi said.
"Right now, he's got the green light [to pitch]," Ricciardi said. "Throwing in a simulated game is pretty good.
"He's ahead of schedule. ... He could hit a setback at some point, but right now, he's doing great."
Marcum will be pitching simulated games on a regular basis, according to the GM, and he likely will throw again on Tuesday. From there, Toronto plans to have Marcum make seven or eight Minor League rehab appearances.
"He'll be 10 months [removed from surgery] July 4 or 5, so he should be out at that point throwing in some Minor League games," Ricciardi said. "Optimistically, we could see Marcum this year. But that's barring any setbacks."
While the Jays would welcome Marcum back this season, Ricciardi is not prepared to rush him to the big leagues even if circumstances -- another blow to Toronto's injury-riddled rotation, perhaps -- make that a tempting proposition.
"If he's ready and he can help us at the Major League level, we'll bring him up, but he's going to determine that clock," the general manager said.
Ricciardi noted that Marcum has had one minor setback so far and was shut down for a week, but he called that "common."
Marcum and McGowan both started the season on the DL, as did right-hander Casey Janssen, who returned in late May but was shelved again on June 17 with inflammation in his right shoulder -- the same shoulder that was surgically repaired in Spring Training of 2007 and forced him to miss all of last season.
Janssen is in Florida, and Ricciardi said the right-hander is doing "OK."
"I don't know what the ETA is, but he's doing OK," Ricciardi explained before adding, "He's still a ways away."
Ricciardi added that Toronto's pitching situation may determine if Janssen returns as part of the rotation or the bullpen. Janssen started his Major League career as a starter in 2006, but he pitched out of the bullpen in 2007. His five appearances for the Blue Jays this season all have been as a starter.
"He came up as a starter. His whole career, he was a starter," Ricciardi noted. "We're the ones who put him in the 'pen. I don't know -- it may be what job's available when he comes up."
Ricciardi also gave updates on right-handers Jesse Litsch and Robert Ray. The GM is hoping Litsch, who underwent Tommy John surgery in June, will be throwing in Spring Training next season and pitching with the Jays less than a year from now.
There had been some uncertainty as to whether Litsch's elbow would require surgery at all, but Ricciardi explained that while initial MRIs did not show ligament damage, a third MRI showed a small tear in the ligament.
"I guess the MRIs, they're not totally conclusive," Ricciardi said. "You get to a point where the guy keeps complaining, you've got to treat the player more than you treat the MRI."
Ray, who made four starts for Toronto after being summoned from Triple-A Las Vegas before being placed on the DL with a shoulder problem in late May, is making "slow" progress, according to Ricciardi.
"He's been checked out. [But] he's not 100 percent," the GM said. "He's able to throw, but he's not ready to get on a mound."
Erika Gilbert is an associate reporter for MLB.com. This story was not subject to the approval of Major League Baseball or its clubs.