Arenado is out of the lineup for Sunday's game against the Brewers.
He'll take a seat for only the third time in the Cardinals' 47 games on the season, paving the way for Edmundo Sosa to pick up a start at third base. Arenado's move to the bench comes after he went 0-for-13 at the dish over the past four contests, dropping his season average to .271.