Snell was removed from the first inning of Wednesday's start against the Reds due to left groin tightness.
Snell went to the clubhouse with trainers after the first inning, and further tests revealed that the veteran southpaw picked up a groin injury during Wednesday's start. He'll need to be evaluated further to determine the severity of the injury, but Fabian Ardaya of The Athletic points out that Snell has a history of left groin/adductor injuries. That puts Snell in danger of missing the rest of the regular season and jeopardizes his availability for the playoffs.