This time it wasn't enough for a victory over a plucky Chicago White Sox side.
Once again, Donaldson homered off Chicago closer David Robertson in the ninth inning, but this time no one was on base. The game-tying solo shot forced an extra frame and the White Sox scored a pair off reliever Roberto Osuna in the 10th for a 5-3 win on Wednesday.
Adam LaRoche drove in Jose Abreu with the go-ahead run and pinch-runner Emilio Bonifacio tacked on an insurance run when he scored on a Gordon Beckham double. Chicago (20-24) ended its four-game losing skid and salvaged the finale of the three-game series.
It was the first loss in four games for Toronto (22-27) and it capped a 5-5 homestand. Robertson (4-1) blew the save in the ninth but came back out for the 10th.
Chicago caught a break in the third inning when right-fielder Ezequiel Carrera lost a fly ball in the bright afternoon sun, allowing two runs to score. The White Sox scratched out another run in the sixth on their way to their second win in nine games.
"We feel like we're playing pretty well," Donaldson said. "I'm not here to make excuses but a ball gets in the sun and scores two runs, that's just baseball. At the end of the day we kept pushing and gave ourselves a chance to win.
"Obviously they ended up scoring a few more runs in the end."
Blue Jays starter Marco Estrada gave up a pair of singles in the third inning and nearly got out of the jam when Melky Cabrera flew out for the second out and Abreu popped up to shallow right field. Carrera got under the ball but couldn't focus on it and it dropped in for a double.
In the sixth, LaRoche singled, moved to second on a grounder and scored when J.B. Shuck flared a ball to shallow centre field.
Chicago starter Jeff Samardzija pitched well enough to prevent a big inning. He allowed eight hits and one unearned run over seven innings while walking one batter and striking out five.
The Blue Jays put a charge into the crowd of 15,463 in the seventh when Kevin Pillar led off with a single and moved to second base on an infield single by Ryan Goins. Both runners advanced on a passed ball but had to stay at their bases when Jose Reyes grounded out.
Donaldson, who scored five times and hit a three-run walkoff homer in Tuesday's 10-9 victory, lashed a ball to the warning track and Pillar jogged home on the sacrifice fly. Jose Bautista followed by driving a ball to deep left field but it hung up for the third out.
Chicago reliever Jake Petricka started the eighth inning but was pulled after one-out singles by Canadian Russell Martin and Chris Colabello. Zach Putnam came on to face pinch-hitter Justin Smoak and he singled to score Martin and move Colabello to second.
Pillar hit into a fielder's choice to put runners on the corners and Ventura brought in left-hander Zach Duke. Pinch-hitter Danny Valencia hit a hard one-hopper that Abreu snared at first base to retire the side.
Donaldson hit his 13th homer of the season in the ninth. It was his fourth homer in three games.
"If (Robertson) could stay away from Donaldson, we'd be all right," said White Sox manager Robin Ventura. "The guy is just on fire. We've got to stay away from him somehow."
The Blue Jays are off Thursday and will kick off a six-game road trip Friday night in Minnesota. Toronto has struggled over the first two months of the season but entered play Wednesday just three games behind first-place New York in the weak American League East division.
"We're feeling pretty good right now," said Blue Jays manager John Gibbons. "There's a long way to go. But we're feeling pretty good."
Notes: Defensive adjustments forced Martin to move to second base in the ninth inning with Josh Thole taking over behind the plate. Martin last played the position on Aug. 20, 2011. ... Estrada allowed three earned runs and eight hits over seven innings. He had two strikeouts. ... The roof was open even though a severe thunderstorm watch was in effect for the area. ... The game took three hours 31 minutes to play.
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