Koss went 0-for-2 with a walk and a stolen base in Monday's 3-0 win over the Brewers.
Casey Schmitt exited Monday's contest with left knee discomfort after hitting a single, and Koss entered the game in his place before stealing second base. The 28-year-old also drew a walk in the fourth inning but was picked off at first. Koss is slashing just .130/.231/.174 with a run scored and a stolen base across 26 plate appearances this season, though he could see more action if Schmitt misses time.