CHICAGO -- Cubs starter Jameson Taillon will be placed on the injured list after exiting Sunday's game against the San Francisco Giants with a left hamstring strain in the top of the second inning.
Taillon, 34, called for the athletic trainer after throwing ball four to Giants third baseman Matt Chapman. A few moments later, Taillon left and was replaced by right-hander Javier Assad.
Taillon will undergo an MRI on Monday to determine the extent of the injury.
"It's nothing I've ever felt," Taillon said after the Cubs lost 2-1 in 10 innings. "Unfortunately, one pitch kind of did it."
Taillon, who has made all 13 of his starts, has a 5.19 ERA after giving up a run in the first inning. He also leads the majors in home runs allowed (20).
He was asked if he thought the injury was serious.
"I don't think it's crazy," he said. "I'm walking around, moving around.
"Hopefully we can keep the arm conditioned and moving around and limit it from being too long."
Taillon's injury is another in a series of ailments for Cubs pitchers that includes Cade Horton (elbow), Matthew Boyd (knee) and Justin Steele (elbow).
Meanwhile, right-hander Edward Cabrera (blister) just came off the injured list Friday, taking the loss in an 18-3 rout by the Giants.
Assad pitched well in relief of Taillon, shutting the Giants out for 6⅓ innings. He could simply take his place in the rotation, though Boyd is due back this week after making two rehab starts at Triple-A Iowa.