Diaz is out of the lineup for Thursday's game against the Tigers.
The Rays haven't indicated that Diaz is dealing with an injury, and despite being one of the team's more productive hitters this season, he'll be on the bench for the third time in four games Thursday. With Diaz's playing time having been scaled back lately, Jonathan Aranda has taken over as the Rays' everyday first baseman, and manager Kevin Cash has rotated a number of different players at the designated-hitter spot.