All three prospects were called up within the past week after Melky Cabrera, Colby Rasmus and Bautista all hit the disabled list with various ailments.
"He'll play, we'll get him in there tomorrow against Andy Pettitte, " Blue Jays manager John Gibbons said of Sierra. "Then we'll just see, we'll match them all up and give them all some playing time. It's an opportunity for some guys, you don't always get those in this business.
"You don't know what extended period of time it's going to be, but getting to the big leagues, some guys never get the opportunity, so take advantage of it."
Pillar and Gose are expected to see the bulk of the playing time in the outfield alongside veteran Rajai Davis. Sierra's opportunities likely will come when Gose sits against left-handed pitching and whenever someone in the starting three needs a day off.
Sierra appeared in 49 games for the Blue Jays last season but has struggled at times with Buffalo this year. He was hitting just .261, but did have 11 homers and 51 RBIs in 100 games for the Bisons.
The high number of injuries can't be used as an excuse for Toronto's underwhelming record this year but it's clear they have taken a toll on the club in recent weeks. In addition to the injured outfielders, the Blue Jays also are without the services of Steve Delabar, Josh Johnson, Dustin McGowan, Brandon Morrow and Juan Perez just to name a few.
"You deal with it," Gibbons said. "It seems to be happening in bunches lately, but that's part of it. Everybody goes through that and you have to show up the next day and play. You have no choice."
Gregor Chisholm is a reporter for MLB.com. Read his blog, North of the Border, and follow him on Twitter @gregorMLB. This story was not subject to the approval of Major League Baseball or its clubs.