BOSTON -- On a team with dangerous hitters like Jose Bautista, Edwin Encarnacion and Josh Donaldson, it was Ezekiel Carrera who played the hero for the Toronto Blue Jays on Saturday night.

Carrera, a .252 hitter, lifted a sacrifice fly in the ninth inning that proved to be the final blow in an important 4-3 victory for the Blue Jays over the Boston Red Sox at Fenway Park.

"Zeke's got that ability, he can just flick a ball," Blue Jays manager John Gibbons said. "That's one of his strengths and he just hung in there, got enough barrel on it."

Kevin Pillar had three RBIs for Toronto (88-73), which tied Baltimore for the top American League wild-card spot after the Orioles' 7-3 loss to the New York Yankees earlier in the day.

The win ensured the Blue Jays will play at least a tiebreaker play-in game, but a victory Sunday would allow Toronto to host the wild-card game.

"I'm not worried about that," Gibbons said. "We want to enjoy this one. They've been hard to come by, so we'll let (others) worry about that."

Chris Young drove in two runs for AL East champion Boston (93-68), which trails its AL Division Series opponent Cleveland by a one-half game. The Indians posted a 6-3 victory over the Kansas City Royals on Saturday.

"Highs and lows," Red Sox right fielder Mookie Betts said. "But I think we played pretty good."

Boston won the regular-season series with Cleveland 4-2, so the Indians must finish one game ahead of the Red Sox to gain home-field advantage. If Cleveland and Boston both win or lose Sunday, the Indians must win a makeup contest in Detroit on Monday to get the extra home game.

Roberto Osuna (4-3) took the win with two innings of one-run ball after blowing a save.

Blue Jays starter J.A. Happ departed after 6 1/3 innings, giving up two runs, four hits and five walks with a strikeout in a no-decision.

Red Sox starter Eduardo Rodriguez surrendered three runs, three hits and five walks but struck out nine in a five-inning no-decision.

The young left-hander has struck out 22 batters in his last 10 1/3 innings in two starts after striking out a career-high 13 his last time out against the Tampa Bay Rays.

Craig Kimbrel (2-6) entered in a non-save situation in the ninth and gave up the decisive run on Carrera's sacrifice fly.

Pillar shot a grounder up the middle into center field with one out in the sixth to allow Russell Martin to score from second base and break a 2-2 tie.

Betts doubled and Hanley Ramirez walked to lead off the Red Sox eighth, leading the Blue Jays to turn to closer Roberto Osuna for a six-out save.

It looked like Osuna would escape with the lead after getting Brock Holt to ground into a double play, but an Osuna balk allowed Betts to trot home from third to tie it.

"That was a pretty obvious one," Betts said of the balk.

"We had the lead then the tying run scores on a balk; I was wondering about the baseball gods," Gibbons quipped.

Boston turned to Kimbrel in the ninth, but the All-Star closer faltered. Kimbrel walked Michael Saunders to begin the inning and Pillar moved him over with a sacrifice bunt.

Kimbrel threw a wild pitch to allow Saunders to move to third and Carrera flied out to left to allow Saunders to score the winning run.

David Ortiz received a standing ovation before working a one-out walk in his first at-bat in the Boston first but was tagged out at second base on Betts' groundout.

Ramirez coaxed another walk from Happ to load the bases for Chris Young, who delivered a two-run single to shallow center field.

Rodriguez mirrored Happ's shaky start, loading the bases with three straight walks to open the Toronto second.

Melvin Upton Jr. struck out looking, but Pillar found the gap in left-center field for a game-tying, two-run single.

Rodriguez escaped the jam with limited damage by getting Carrera and Devon Travis to strike out swinging.

Ortiz hit a one-out single to right in the fifth and was removed for pinch-runner Travis Shaw.

He received another ovation and tipped his helmet to the crowd as he lumbered back to the dugout. Ortiz finished the night 1-for-2 with a walk.

NOTES: Boston C Christian Vazquez was behind the plate for LHP Eduardo Rodriguez's second straight start after catching a major league-record 23 strikeouts, including a career-high 13 for Rodriguez, last Sunday against the Rays at Tampa Bay. Manager John Farrell hinted that Vazquez could be in the mix for the second catcher spot on the postseason roster. "There are some areas on our roster for decision making yet," Farrell said. ... Red Sox SS Xander Bogaerts celebrated his 24th birthday on Saturday. Only Ted Williams (714), Bobby Doerr (661) and Tris Speaker (547) had more hits before turning 24 in franchise history than Bogaerts (524). ... Former members of the New England Patriots and Boston Bruins and the current Boston Celtics roster were on hand for a pregame ceremony honoring retiring Boston DH David Ortiz. ... Blue Jays RHP Aaron Sanchez (14-2, 3.06 ERA) opposes Red Sox LHP David Price (17-9, 4.04) in Sunday's regular-season finale.