The Chicago Cubs placed right-hander Jameson Taillon on the 15-day injured list Thursday with a left groin strain.

The move is retroactive to Monday for Taillon, who completed a brief bullpen session without issue on Wednesday. That said, the Cubs opted to exercise caution.

"The way I had this presented to me was like, 'We're playing for the long haul here,'" Taillon said Wednesday. "And, 'You'd be a bad teammate if you really pound the table and push through this and screw the team for what's really important here.' If I make something worse and I miss the last couple weeks of September or the playoffs and all that, that's not the right thing to do.

"Just trying to have that longer-term view, that big-picture view is important here."

Taillon, 33, has posted a 9-6 record with a 4.15 ERA in 19 appearances (all starts) this season. He missed all of July and the beginning of August with a right calf strain.

Also on Thursday, Chicago recalled fellow right-hander Javier Assad from Triple-A Iowa.

Assad, 28, is 0-1 with a 3.86 ERA in three appearances (all starts) with the Cubs. He has a 2.45 ERA in five appearances (all starts) in two separate levels in the minors this season.