Atlanta manager Walt Weiss said Thursday that Thomas (side) will be placed on the 10-day injured list, Mark Bowman of MLB.com reports.
Thomas had to be scratched from Thursday's lineup against the Rays after tweaking his left side pregame. Though he will be eligible to return later this month, it's an injury that could end Thomas' regular season. He's gone just 7-for-41 with one home run in 21 contests since joining Atlanta at the trade deadline.