Zimmermann was terrific for the Tigers last April, but the rest of his season was ruined by neck problems. He labored early against Boston but eventually made it through the middle of the game comfortably.
"Everything feels good. Neck is great," the right-hander said. "First game, so take it slow and move forward."
Zimmermann (1-0) allowed a run and four hits. Boston led 1-0 when Iglesias tied it in the third with a solo shot to left. McCann's homer in the fifth put Detroit up 2-1, and the Tigers added two more runs that inning.
Eduardo Rodriguez (0-1) allowed four runs and five hits in five innings for the Red Sox, who have had several players out sick recently. Hanley Ramirez and Mookie Betts didn't play Saturday. Outfielder Andrew Benintendi played, but manager John Farrell said he threw up during the game.
"We're hopeful that that was just a one-time deal," Farrell said. "We'll see how he feels when he comes in tomorrow."
Zimmermann allowed a sacrifice fly by Jackie Bradley Jr. in the second, and the Red Sox loaded the bases with one out in the third. That rally ended when Benintendi grounded into a double play.
After McCann's homer gave the Tigers the lead, Iglesias added an RBI double in the fifth and scored on Ian Kinsler's single.
Bradley made a spectacular play in the eighth on a drive by Nicholas Castellanos, racing over from center field to right-center and catching the ball before slamming into the wall.
"It's a joke. He's making plays that I don't know if anybody else can make," Boston second baseman Dustin Pedroia said. "It's pretty special the routes he's taking and the way he's getting the ball."
In the ninth, Bradley appeared hurt when he hit a flyout to left, rounded first and went down holding his right knee. He was eventually able to walk off the field and seemed OK.
Left-hander Kyle Ryan was activated from the paternity list before the game and made it through a scoreless eighth inning for the Tigers. He had quite an ordeal getting from Florida to Detroit, though.
"His flight got canceled last night," Detroit manager Brad Ausmus said before the game. "They couldn't find any flights to Detroit until Monday, so he flew to Columbus and he's currently in a car."
Ryan said he took a car service from central Ohio to Detroit.
"I showed up about an hour before the game," he said.
Boston's Pablo Sandoval hit a foul ball in the second inning that shattered a glass barrier at the front of the upper deck behind home plate. Some debris fell into the lower seating area, but nobody appeared hurt.
Red Sox: LHP David Price (elbow strain) threw out to 120 feet in what Farrell described as "another consistent work day." ... LHP Drew Pomeranz (forearm strain) remains on track to start Tuesday against Baltimore.
Tigers: Ausmus said OF J.D. Martinez (sprained right foot) was able to swing Friday.
Red Sox: RHP Rick Porcello (1-0) takes the mound against his former team when he faces Detroit on Sunday.
Tigers: LHP Daniel Norris makes his first start of the season.
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