Diaz will start at first base and lead off in Sunday's game against the Giants, Josh Tolentino of The Athletic reports.
Diaz will occupy the leadoff spot for the third time this season, with each of those assignments coming against left-handed pitching. The Rays are expected to continue to deploy a platoon atop the order for the foreseeable future, with the lefty-hitting Austin Meadows setting the table on most occasions.