Alvarado signed a major-league contract with the Pirates on Tuesday, Noah Hiles of the Pittsburgh Post-Gazette reports.
Alvarado spent the majority of the 2024 season with the Marlins' Triple-A affiliate, where he posted a 2.49 ERA and 1.40 WHIP alongside a 70:36 K:BB over 47 innings. He has yet to appear in a major-league game, but the Pirates seem to like the 25-year-old righty enough to hand him a spot on their 40-man roster, and he'll have an opportunity to make the Buccos' Opening Day bullpen during spring training.