The Yankees reassigned Underwood to minor-league camp Wednesday.
Underwood, who signed a minor-league deal with the Yankees in December, had been attending camp as a non-roster invitee. The 29-year-old reliever made 20 appearances out of Pittsburgh's bullpen in 2023, ringing up a 5.18 ERA and 1.44 WHIP across 24.1 innings. He's likely to begin the upcoming season with Triple-A Scranton/Wilkes-Barre.