TORONTO -- Ryan Dempster remained undefeated in his homeland.
Dempster, from British Columbia, is 6-0 in 10 starts in Canada, the first nine in Montreal.
"I'm looking for more expansion teams in Canada," he said jokingly. "That's kind of the goal. Maybe Vancouver will get a team, or Winnipeg or something, so I can hopefully keep that going."
Dempster is the first Canadian-born Red Sox starter to win in Canada since Rheal Cormier beat the Blue Jays in Toronto in 1995.
"It was fun to get out there and pitch in the Rogers Centre," Dempster said. "I grew up watching the Blue Jays in the SkyDome so it was a lot of fun."
Dempster (2-2) allowed one run and four hits in six innings. The right-hander, who walked three and struck out four, retired 10 of the final 11 batters he faced. That streak began with a double-play grounder to escape a bases-loaded jam after three walks in the third.
"I was able to make a couple of big pitches, especially with the bases loaded, and get out of my own mess I made," he said.
Winless in his first four starts this season, Dempster posted his first victory by beating Houston a week ago.
"He doesn't give in," Red Sox manager John Farrell said. "He didn't have his best stuff overall tonight but he uses the whole count when he needs to and he's got the knack to not let the game speed up on him and try to reach back and just go with sheer velocity."
Hanrahan got the call in the ninth because regular closer Andrew Bailey was unavailable.
"He's felt some discomfort in the biceps," Farrell said of Bailey. "He got on the mound a little bit before the game yesterday and felt the discomfort. It was still there today so he was unavailable."
Bailey said he first felt sore after pitching an inning against the Astros on Sunday, but described the pain as "very minor, nothing crazy."
"We're just being very cautious with it," Bailey said. "Shouldn't be more than a couple of days. We're just letting it die down."
Hanrahan, who was activated off the DL Tuesday, said Farrell told him during batting practice that Bailey was unavailable, and to be ready for the save opportunity if it came up.
"We're a better team when Bailey and I are both healthy," Hanrahan said. "Hopefully he'll only be down for a day or two."
Boston improved its major league-best road record to 9-3 and won its seventh series in nine tries this season.
The Red Sox have won eight of 10 and are 20-8 overall, their best start since opening 20-7 in 2002.
Lawrie connected leading off the bottom of the first, his third homer of the season and the third leadoff shot of his career.
Napoli's double was his ML-leading 22nd extra-base hit.
Blue Jays left-hander J.A. Happ allowed two runs and three hits in 3 2/3 innings, his shortest start of the season and his shortest since May, 2009. Happ (2-2) matched a career high with seven walks and struck out two.
"There's a line between not giving in and making quality pitches and I was constantly on the wrong side of that line tonight," Happ said. "I made it tough on myself."
"I think (Happ) just lost his release point," Blue Jays manager John Gibbons said. "He's the type of pitcher where he pitches up in the zone and sometimes he loses that."
Toronto loaded the bases in the seventh but Tazawa struck out Adam Lind to end the threat.
The roof at Rogers Centre was open for the first time this season. ... Rasmus' first hit was the 500th of his career. ... Red Sox DH David Ortiz got the day off. ... Toronto placed RHP Josh Johnson (right triceps) on the 15-day DL, retroactive to April 29, and recalled Lincoln from Triple-A Buffalo. LHP Ricky Romero was recalled from Class-A Dunedin to start against Seattle on Friday, with RHP Justin Germano designated for assignment. ... Red Sox OF Shane Victorino (back) felt fine after taking batting practice and was available to pinch hit. Red Sox manager John Farrell said Victorino could return to the starting lineup for Friday's game at Texas. ... Boston LHP Franklin Morales (back) played catch on flat ground for the second straight day Thursday and is expected to throw a bullpen session in Texas this weekend. Morales went on the DL March 31.