Valdez will be recalled from Triple-A Round Rock to start Sunday's game against the Angels, Jake Kaplan of The Athletic reports.
Valdez was previously a candidate to start Saturday's contest, but he'll instead take the mound in the series finale. The 25-year-old has a 5.58 ERA, 1.58 WHIP and 45:26 K:BB over 50 major-league innings this season.