Cook is out of the lineup for Wednesday's game against the Brewers.
Cook will hit the bench after he went 3-for-14 with a solo home run and a stolen base while starting each of the past four games at four different positions (first base, left field, right field and center field). First base could end up being the primary home for Cook over the final four games of the season after the Pirates moved Rowdy Tellez off the 40-man roster Tuesday.