ST. LOUIS — Right-hander Jake Westbrook is being placed on the 15-day disabled list by the St. Louis Cardinals because of a lower back strain.

The move, announced on Friday, is retroactive to Thursday.

Manager Mike Matheny said rookie left-hander Tyler Lyons will take Westbrook’s spot in the rotation Monday against Cincinnati.

Rookie right-hander Carlos Martinez was recalled from Triple-A Memphis and will be used in relief.

The Cardinals do not believe the injury is season-ending and Westbrook said that’s the biggest reason to place him on the DL “to kind of knock it out, get me back to where I don’t have any of those nagging things, get back to full strength.”