Morrow has an entrapped radial nerve that will keep him from throwing for the next six weeks. Renowned orthopedic surgeon Dr. James Andrews made the diagnosis, which the team announced Thursday.
"He was feeling better, but he wasn't making a whole lot of progress," manager John Gibbons said. "They recommended six weeks off, and when you look at six weeks, how much time is left? But the thinking is that they want him, hopefully when that six weeks is up, he starts getting on the mound so that when the year is over he's at least thrown from the mound doing something. So he goes in the off-season knowing where he's at and feeling good about it, anyway."
Morrow went 2-3 with a 5.63 ERA in 10 starts before leaving the Blue Jays' game May 28 after two innings. Several MRIs were taken on the right-hander's sore arm, but all that doctors found was inflammation, according to general manager Alex Anthopoulos.
Because of that uncertainty, Anthopoulos said Wednesday afternoon that he wasn't very optimistic about Morrow's status.
"I don't know enough about the severity," Anthopoulos said. "I just know that it's not safe for him to go out there."
Morrow had been throwing side sessions while rehabbing in Dunedin, Fla., but Andrews prescribed six weeks off. That would take the 28-year-old to September, when it would be difficult for him to get ramped back up for big-league action.
"After six weeks you figure it's got to be better, you would hope," Gibbons said. "But I'm no doctor."
The Blue Jays might not know for sure about Morrow's future until spring training when he faces live hitters again, but they hope he'll be able to test things out in the fall.
"If he throws after six weeks and he's feeling good and it's all behind him and he gets on the mound, I mean it wouldn't be actual game competition but he'd be airing it out," Gibbons said. "You'd have a better idea, anyway."
Anthopoulos also said he likes the flexibility afforded the Blue Jays by Brett Lawrie's ability to play second and third base. But for the majority of at least the short-term future, Lawrie will be a corner infielder.
Gibbons stopped short of saying the Lawrie at second base experiment was over for good, but he penciled the 23-year-old in at third base again for Thursday's series opener against the Houston Astros and plans on keeping him there.
"We always have a right to change our mind," Gibbons said. "It's not definite where he's going to be only (at third base), but we'll see how that plays out."
Gibbons cited Lawrie's defensive plays Wednesday night as his reasoning, saying, "I'm dumb, I'm not stupid. I've seen him be good, he's always been good."
Mark DeRosa might still see some time at third, which would require Lawrie to move over to second.
Lawrie is hitting .208 this season — .215 at third base and .158 at second. According to Gibbons, Lawrie is OK with moving back and forth.
"He said, 'I'll play anywhere, whatever the team needs.' That was his answer," Gibbons said. "I said, 'We don't want to get into the habit of moving you around, but I think it helps our flexibility and who knows what it might address down the road.'"