Ex-Fisher Drabek's win comes at expense of Sox
Arencibia's two-run single keyed a three-run sixth inning as Toronto ended a two-game losing streak before a crowd of 26,351 at Rogers Centre.
Encarnacion drove in a run in the first with an infield single and hit his first home run of the season in the seventh against reliever Michael Bowden.
Adrian Gonzalez drove in all three Boston runs, two in the ninth with a double.
The Blue Jays (3-2) and Red Sox (1-4) play the rubber match of the three-game series Wednesday afternoon.
Drabek (1-0) allowed three hits, all doubles, and three walks while striking out four in his first major league start since last June 12. The former New Hampshire Fisher Cat was demoted after that start to Class AAA Las Vegas.
Hard-throwing Boston right-hander Daniel Bard (0-1), making his first career major league start after three seasons as a reliever, allowed five runs, eight hits and one walk while striking out six over five innings. He faced two batters in the sixth.
Drabek was cruising with a two-hitter through five innings, but he walked Jacoby Ellsbury to open the sixth, and Dustin Pedroia doubled the runner to third.
Gonzalez hit a sacrifice fly to right fielder Jose Bautista, whose throw to third beat Pedroia, but third baseman Brett Lawrie dropped the ball. David Ortiz walked to end Drabek's outing at 91 pitches.
Jason Frasor ended the inning by coaxing Kevin Youkilis to ground into a double play.
Bard left the game in the sixth after a leadoff walk to Encarnacion, a stolen base and an infield single by Lawrie put runners at the corners.
Lawrie stole second against left-handed reliever Justin Thomas, who then walked Eric Thames to load the bases. Arencibia singled to center to score two runs. Colby Rasmus made it 6-1 with a sacrifice fly to left.
After Encarnacion's homer in the seventh increased the lead to six, Boston loaded the bases with two outs in the ninth against Casey Janssen. Gonzalez doubled in two runs.
The Blue Jays scored a run in the first inning on an infield single to shortstop by Encarnacion. It brought home Yunel Escobar, who led off with a single and took third on Adam Lind's two-out double.
Escobar led off the third with a single, took second on Kelly Johnson's single and scored on Lind's single. Lawrie's two-out single increased the lead to 3-0. Bard ended the inning by striking out Eric Thames.
Drabek retired nine batters in a row after allowing a double to Youkilis and a walk to Ryan Sweeney with one out in the second. Cody Ross ended that string with a one-out double in the fifth.