Velasquez was placed on the 15-day injured list with a left groin strain Friday, retroactive to May 31.
The 29-year-old was slated to start Friday's game against the Rays, but Davis Martin will step in as the starter after he was recalled from Triple-A Charlotte. It's not yet clear how much time Velasquez will miss, but it's possible he'll take on a bullpen role once he returns to action since Lance Lynn (knee) is closing in on a return.