The Cardinals placed Lynn on the 15-day injured list Wednesday with right knee inflammation.
Lynn picked up a win Tuesday, holding the Pirates to one run over six innings. However, his knee has been an issue off and on throughout the 2024 campaign, and the Cardinals have decided it was for the best to shut him down. St. Louis has been using a six-man rotation lately, so they could either go back to a traditional five-man setup for slide Steven Matz or Michael McGreevy into Lynn's spot.