Betts belted two home runs and matched his career best with eight RBIs Sunday afternoon as the Red Sox trounced the Blue Jays 15-1 to complete a sweep of the three-game series.
Betts had three-run and two-run homers, a two-run single and an RBI single as the Red Sox won their fourth game in a row.
"Today felt pretty good," Betts said. "I got some good pitches to hit and just tried to put a good swing on it and hope for the best. When you get to the plate, you're just expecting a good pitch to hit and you're ready for it. Today I was just more ready than other days."
Hanley Ramirez added three hits, including a two-run homer, and three RBIs for the Red Sox (47-35), who outhit the Blue Jays 21-5.
"The way Hanley has swung the bat in the middle of the order, that's a major presence for us," Red Sox manager John Farrell said.
Drew Pomeranz (8-4) allowed five hits, two walks and one run in six innings to win his second straight start.
"He's been strong, he's been very consistent," Farrell said. "His presence and way he's gone about these last 10 starts in particular have been strong."
Pomeranz has a 3.57 ERA in his past nine starts.
Fernando Abad replaced Pomeranz in the seventh and allowed one walk in three innings to pick up his first save of the season.
The Blue Jays (37-44) completed a six-game homestand with one win. They've lost four in a row.
"We're not hitting, really, it's pretty obvious," Blue Jays manager John Gibbons said. "We've been cold the last few days, it'll change."
Blue Jays starter Joe Biagini (2-8) allowed two homers among 10 hits, two walks and seven runs while striking out seven in 5 1/3 innings. His ERA climbed to 5.03.
"There were times when he was really, really good today," Gibbons said. "He was getting ahead of guys, then it was like he was trying to make that perfect pitch and the count swings back in their favor. Betts burned him a couple of times. He did the damage."
Blue Jays catcher Russell Martin said, "We played hard, they were just better than us today. I don't see it as rock bottom or anything like that. Today is just a day where it didn't go our way. They found holes, they battled tough with two strikes, they made us work.
"We didn't play well today, we really didn't have a good series at all. We got outplayed. So we've got to bounce back, head to New York (for a series against the Yankees), forget about this stuff and get ready for the next game."
The Red Sox scored a run in the first inning on a pair of two-out walks and an RBI single by Ramirez that extended his hitting streak to seven games.
They scored another run in the second inning on a triple by Tzu-Wei Lin and a single by Betts.
A sacrifice fly by Steve Pearce gave Toronto a run in the second. It scored Justin Smoak, who led off with a single, moved to second on a walk to Kendrys Morales and took third when Troy Tulowitzki flied out to center.
Lin and Deven Marrero bunted for singles to open the fourth and Betts homered to put Boston into a 5-1 lead.
Betts hit his 15th homer of the season after Marrero singled to make the score 7-1.
Aaron Loup replaced Biagini and completed the sixth before Glenn Sparkman took over for the seventh inning.
Sparkman coughed up seven hits and seven runs in one-third of an inning.
Jeff Beliveau replaced Sparkman and allowed the 12th homer of the season by Ramirez.
NOTES: Boston SS Xander Bogaerts (left groin tightness) was a late scratch from the lineup and was listed as day to day. ... Boston manager John Farrell returned after watching his son Luke's major league pitching debut Saturday with the Royals in Kansas City. ... Boston traded minor league 1B Nick Longhi to the Cincinnati Reds for international amateur signing bonus pool space. ... Toronto acquired minor league OF Eduard Pinto from the Texas Rangers for RHP Jason Grilli, who had been designated for assignment, and cash considerations. ... Boston RHP Rick Porcello (4-10, 5.06 ERA) will start the opener of a three-game series Monday against the Rangers in Arlington, Texas. Texas had not named a starter. ... Toronto opens a three-game series at Yankee Stadium on Monday with RHP Marcus Stroman (8-4, 3.41) facing Yankees RHP Masahiro Tanaka (6-7, 5.56).