Price (1-2, 3.75 ERA) has not pitched since May 2 because of tendinitis in his pitching elbow.
The left-hander will be facing Blue Jays right-hander Edwin Jackson (0-0, 3.60), who set a major-league record of playing for 14 teams when he made his first start for the Blue Jays in San Francisco against the Giants last week.
One of the reasons Price is making his return on the road Monday, instead of possibly pitching in Boston over the prior weekend, is that Toronto's Rogers Centre has a retractable roof.
"He's doing better," Red Sox manager Alex Cora said recently. "As you know, probably the weather (in Boston) is what the weather is. I think that controlled environment in Toronto is better. And also two bullpens in between the start. Instead of going from zero to the start, he gets two bullpens in and then he'll go from there."
Price -- who helped the Blue Jays win the American League East title in 2015 when he went 9-1 with a 2.30 ERA as a midseason acquisition from the Detroit Tigers -- has had success at Rogers Centre, where he is 12-1 with a 3.31 ERA in 17 career starts.
Last season, Price went 4-0 with a 2.63 ERA overall against Toronto. This will be his first appearance against the Blue Jays this season.
In his career against the Blue Jays, he is 21-3 with a 2.43 ERA in 30 games (29 starts) and at Toronto against the Blue Jays he is 8-0 with a 3.73 ERA.
"He can give us 15 to 18 outs," Cora said. "We'll see how it plays out."
It is possible that Sandy Leon will be behind the plate for Price. Leon missed the weekend games; he was on paternity leave because of the birth of his daughter.
The teams split two games at Fenway Park in early April.
Both teams are coming off wins on Sunday afternoon. The Red Sox ended the Houston Astros' 10-game winning streak 4-3 in a duel between the past two World Series champions.
The Blue Jays gained a split in their four-game series in Chicago with a 5-2 victory over the White Sox. Vladimir Guerrero Jr. hit a two-run homer in the eighth inning to break a 1-1 tie. Danny Jansen added a two-run homer in the ninth as the Blue Jays completed their road trip 3-3.
Jackson did not figure in the decision in San Francisco Wednesday, a 4-3 Giants win. Jackson worked five innings, allowing three runs (two earned) and six hits and left a 3-3 game.
Jackson last faced the Red Sox in 2016 and is 3-4 with a 4.64 ERA in 15 games (12 starts) against them.
The 35-year-old is in his 17th season and has a 104-123 career record.
"It says I have a lot of perseverance," Jackson said. "Some of those teams had situations which would make other people want to go home and quit and cry, but for me, it's like the tougher it gets, the harder I work."
Blue Jays manager Charlie Montoyo seems happy to have him on the team.
"He's going to give you all he's got every time he takes the mound, like he did (Wednesday)," Montoyo said.
--Field Level Media