BOSTON — Mookie Betts has proven he can turn on a fastball in his brief time in the majors. He didn’t miss one for his winning hit.

Betts hit a game-ending RBI single to lift the Boston Red Sox to a 6-5 victory over the Toronto Blue Jays on Monday night.

With one out in the bottom of the ninth, Xander Bogaerts and Ryan Hanigan singled off Miguel Castro (0-2) before moving up on a wild pitch. Betts then lined a 96-mile per hour fastball through a drawn-in infield – to the left of shortstop Jose Reyes – for his third hit of the night.

“He throws 100, so I figured I had to get ready for that,” Betts said. “I got a decent pitch to hit.”

Red Sox Manager John Farrell has seen how well Betts hits hard throwers since getting called up last season. The 22-year old center fielder made the club with a strong spring training. “When he generates that rhythm, the bat speed is there,” Farrell said.

Pablo Sandoval homered for the second straight day for Boston, hitting a solo shot before leaving the game with a sore neck. He also had a two-run single.

The Red Sox have won the opener of each of their seven series this season.

Russell Martin had a two-run double and rookie Devon Travis belted his sixth homer for the Blue Jays, who were coming off a three-game sweep against Tampa Bay on the first leg of their 10-game trip.

“It’s tough,” Blue Jays Manager John Gibbons said.

“It wasn’t a great lead for this ballpark. We had a nice little lead. They just kept chipping away, chipping away. They’re dangerous. They got us there at the end.”

Koji Uehara (2-1) worked a perfect ninth for the win.

Trailing 5-4 in the eighth, the Red Sox loaded the bases and David Ortiz was walked intentionally before Hanley Ramirez hit a tying sacrifice fly. Left fielder Dalton Pompey saved at least one run with a diving grab in the gap. Third baseman Josh Donaldson ended the inning by making a leaping grab of Daniel Nava’s liner.

Boston’s Joe Kelly struck out 10 in six innings, but gave up five runs and five hits.

“Up and down is exactly how you put it,” Kelly said of his start. “These guys are a very good hitting baseball team. When you don’t make pitches, they make you pay for it.”

Toronto starter Aaron Sanchez allowed four runs and struck out seven in 52/3 innings.

“It’s frustrating, they score three and I give them two right back in the first,” Sanchez said.

The Blue Jays jumped ahead 3-0 in the first on an RBI single by Travis and two-run double by Martin.

Boston got two back in the bottom of the inning on Sandoval’s two-run single.

Travis homered into the Green Monster seats in the third, making it 4-2. Kevin Pillar added an RBI single.

The start of the game was delayed 33 minutes by rain.

NOTES: Mike Napoli was out of the lineup because he was sick. … OF Rusney Castillo is expected to DH for Triple-A Pawtucket on Wednesday. He has been sidelined with a shoulder injury since spring training.

Sandoval made a nice headlong, belly-flop grab on Pompey’s soft liner on an attempted sacrifice in the fourth inning. He homered in his next at-bat and then sat out in the top of the sixth.