The Royals recalled Thomas from Triple-A Omaha on Monday.
Kansas City optioned right-hander Jose Cuas to Triple-A to clear a spot in the bullpen for Thomas, who will provide the club with a left-handed option who's capable of covering multiple innings. The 28-year-old has yet to debut for the Royals but has gotten off to a brutal start to his time in the big leagues. Between stops with Milwaukee in 2025 and Atlanta in 2026, Thomas has been rocked for 27 runs -- all earned -- on 27 hits and eight walks in just 11.2 innings over four total relief appearances.