Brian McCann hit two home runs, including a solo shot in the 10th inning that lifted the Atlanta Braves over the Blue Jays 7-6 on Tuesday.
McCann's winning homer came off Thad Weber, who was pitching because closer Casey Janssen was unavailable. Janssen, who had shoulder surgery last November and has not pitched since May 22 against Tampa Bay, said his shoulder was "a little tender."
Manager John Gibbons said he hoped Janssen would be ready to return Wednesday.
Blue Jays starter Brandon Morrow left after two innings with soreness in his forearm. He did not pitch between May 5 and May 18 because of neck and back soreness and of his 47 pitches against the Braves, only three were above 90 mph.
"We don't think it's much of an issue and the doctors don't think it's much of an issue," Blue Jays manager John Gibbons said. "We took him out as a precaution."
Morrow said he first felt sore in his last start, May 23 against Baltimore, and had hoped it wouldn't bother him against the Braves.
"It wasn't explosive," Morrow said. "The ball wasn't coming out of my hand really well. It was just like there wasn't anything in there."
McCann and Gattis hit back-to-back homers off Ramon Ortiz in the sixth, giving the Braves a 6-5 lead, the fifth time this season Atlanta has hit consecutive home runs, but Blue Jays tied it on J.P. Arencibia's RBI double in the seventh.
McCann connected for a leadoff drive in the 10th against Weber (0-1), his sixth home run. It was McCann's first multihomer game of the season and the ninth of his career.
Jordan Schafer also homered for the Braves.
Cory Gearrin (2-1) pitched one inning for the win and Craig Kimbrel celebrated his 25th birthday by finishing for his 16th save in 19 chances.
Atlanta scored three times in the first, taking advantage of some sloppy defensive play by the Blue Jays. Freeman opened the scoring with an RBI single and a second run scored on Jose Bautista's throwing error from right field. One out later, Freeman scored on a throwing error by first baseman Edwin Encarnacion.
Toronto answered with four in the bottom half against Maholm. Encarnacion hit an RBI double, Mark DeRosa's double scored two runs and Colby Rasmus singled home a run.
"The first inning wasn't too great on either side," McCann said.
Atlanta tied it again in the second on a two-out homer by Schafer.
Bautista made it 5-4 in the fourth by hitting a 62 mph slow curve from Maholm over the left-field bullpen for his 12th home run.
"Tip your cap, he stayed back on it well," Gattis said. "He didn't miss it."
Maholm allowed five runs and matched a season-high with 10 hits in six innings.
Gattis led off the sixth with his 12th homer and second in two days, tying it at 5. McCann followed with a drive to right to put the Braves ahead.
Toronto tied it again against Anthony Varvaro in the seventh. Bautista led off with a double and scored on a one-out double by Arencibia. Luis Avilan came on after DeRosa walked, and Arencibia was doubled off second on Rasmus' flare to shortstop, ending the threat.
Atlanta used a walk, a single and a wild pitch to put runners at second and third for Gattis in the ninth, but he struck out against Steve Delabar.
NOTES: Following the game, Toronto optioned Weber to Triple-A Buffalo and designated Ortiz for assignment. The Blue Jays will make corresponding moves to add two pitchers on Wednesday.... Blue Jays 3B Brett Lawrie, who left Monday's game with a sprained left ankle, was held out of the lineup, with DeRosa starting. Gibbons said Lawrie's ankle was still stiff and swollen. Lawrie is day to day. ... Braves OFs B.J. Upton and Justin Upton were both held out of the starting lineup. ...The Braves and Blue Jays begin a two-game series in Atlanta on Wednesday night. Toronto's Esmil Rogers (1-2) faces Kris Medlen (1-5) in the opener.