Morrow hasn't started since June 11 against the Nationals, a game he was forced to leave after making just six pitches. Morrow was Toronto's best pitcher at the time of the injury.
"It has been a lot longer than I would have hoped, but it was one of those injuries that you had to play it by ear until you're feeling good and strong," said Morrow, who will be limited to 85-95 pitches on Saturday. "I'm feeling good and strong now, got all my work in during my rehab assignment and I'm ready to go."
In 13 starts, Morrow is 7-4 with a 3.01 ERA and, despite his time on the shelf, has the second most complete-game shutouts in the Majors with three. With the exception of his abbreviated outing against Washington, Morrow allowed no more than one earned run in eight of his 12 starts.
The 28-year-old, who will be facing the Orioles for the third time this season, has gone 1-0 with a 3.38 ERA over 13 1/3 innings against his division rivals.
Toronto is hoping Morrow can help snap the team's six-game losing skid, which includes a sweep at the hands of the Tigers to kick off the Blue Jays' nine-game road trip.
Baltimore will counter with rookie Steve Johnson, who will be making his second career start. Johnson replaces Wei-Yin Chen, who was given an extra two days of rest, as was fellow starter Miguel Gonzalez.
Johnson last pitched in relief on Wednesday night, tossing an inning in the Orioles' loss to Texas.
"We felt all along that's what we hoped to do," manager Buck Showalter said of giving Johnson another start. "When we made the evaluation with Chen and Miguel, we need to give them a little extra time. As long as we didn't have some emergency where Steve had to pitch really extended there in Texas, it actually worked out perfect. The inning he threw, couldn't have hoped for a better situation for him to get some work in."
The 24-year-old righty is 1-0 with a 3.24 ERA in four games. In his first Major League start on Aug. 8, he lasted six innings and allowed two runs on five hits while striking out nine to pick up the victory.
Blue Jays: Escobar set to rejoin team
Yunel Escobar is the latest Blue Jays player set to rejoin the team in Baltimore.
The shortstop, who missed three games after being placed on the paternity list, will be back with the Blue Jays for Saturday's contest.
Escobar is batting .246 with seven home runs, 39 RBIs and a .619 OPS this season.
First baseman David Cooper, who was forced to leave Wednesday's game against the Tigers with back and neck discomfort, may also be back in the lineup Saturday.
Bautista went 0-for-4 in his return to Toronto's lineup. The two-time defending home run champion ranks second on the team, behind Edwin Encarnacion, in home runs (27) and OPS (.894).
The three-time All-Star hadn't played since leaving a July 16 game against the Yankees with left wrist discomfort in the middle of an at-bat.
Orioles: Davis continues hot hitting vs. Toronto
Chris Davis blasted a career-high three home runs in Baltimore's 6-4 victory over Toronto on Friday night, becoming the seventh Orioles player in franchise history to hit three in a home game.
The three homers set a career high for Davis, who now has 23 on the season to go along with a career-high -- and team-leading -- 64 RBIs.
Davis has done a lot of damage against the Blue Jays this season. The 26-year-old is batting .400 (14-for-35), with eight runs scored, seven homers and 11 RBIs.
He has five homers in his past five games.
Adam Jones extended his season-long home run drought to 25 games in Friday's contest against the Blue Jays. Jones still leads the Orioles with 24 homers.
Closer Jim Johnson recorded his Major League-tying 39th save of the season Friday after striking out two in a clean ninth.
Friday's contest marked the first of nine games the Orioles and Blue Jays play against each other the rest of this season.
The Blue Jays have lost 12 of their last 14 road games, including seven straight.
Toronto has scored 19 runs over its past eight games and more than five just once over its last 17.
J.J. Hardy and Jones have each hit two career home runs against Morrow, while Davis has gone deep once. Jones is batting .364 with six RBIs and 1.098 OPS in 22 at-bats versus Morrow.
Baltimore remains tied with Oakland for the second American League Wild Card spot, while Detroit trails both by one game.