ST. LOUIS – Aaron Sanchez is slated to throw a side session Friday with the target of a Sunday return, something that would allow the Toronto Blue Jays to fill a hole in their rotation created by Thursday’s doubleheader.

The bullpen, Sanchez’s second since having a quarter of his fingernail removed to alleviate his blister issues, will be the key factor in the decision, said manager John Gibbons.

The plan is for him to throw it without protective tape on his finger. All his throwing to this point has been with it on but he can’t have any foreign substance on his finger during games.

If he can start Sunday, Marco Estrada would be pushed back to Monday in New York against the Yankees, which would have been Mat Latos’ day. Either Latos or Casey Lawrence would follow Tuesday with Marcus Stroman on Wednesday.

J.A. Happ isn’t yet a consideration as he continues to recover from inflammation in his left elbow. While his ligament is believed to be sound, the irritation caused from bone on bone contact in the elbow is taking time to dissipate, with the hope that he can resume throwing in the next three or four days.

“Happ, it’s just a holding pattern,” said Gibbons. “He’s just not ready to crank it up just yet.”

SHORT HOPS

Closer Roberto Osuna has surrendered runs in consecutive appearances and three of his past four outings heading into Thursday’s action, with inconsistent usage seen as a primary culprit. “To be honest, I just think he needs more work,” said John Gibbons. “But there’s that fine line – how do you get him that work? He was banged up early, and you’ve seen it, you give a guy work, next thing you know there are three games in a row he’s got a chance to save something.” … Steve Pearce didn’t start the first game of Thursday’s doubleheader in favour of Ezequiel Carrera and while he was slated to start the second, it would mark just his third time in the lineup during the seven-game road trip. “Zeke’s been swinging it,” said Gibbons. “We don’t want to limit him in a platoon, but if the other guy is swinging it, we’re trying to score runs. … (Pearce) has been productive. He’s been pressing big-time.” … Troy Tulowitzki is swinging a bat but not running as he recovers from a strained right hamstring. There’s no timeline for his return or that of Josh Donaldson, who also is yet to run but continues to progress with his strength exercises on his strained right calf.