The Astros acquired Rooney from the Marlins in exchange for cash considerations and added him to the 40-man roster and 26-man active roster ahead of Sunday’s series finale in Boston.
Right-hander Luis Contreras was optioned to Triple-A Sugar Land to make room in the bullpen for Rooney, who has spent the last seven-plus seasons in the minors and will be making his MLB debut if and when he gets into a game. A 28-year-old southpaw, Rooney posted a 2.45 ERA, 1.27 WHIP and 45:23 K:BB in 33 innings over his 33 appearances out of the Triple-A Jacksonville bullpen in 2025.