Castro (0-1) allowed a run on one hit and two walks in one-third of an inning to take the loss Friday against Tampa Bay.
Castro got Yandy Diaz to fly out to start the ninth inning, but he allowed the next three batters to get aboard. Reliever Aaron Loup entered the game and allowed a walkoff single to Brett Phillips, with the decisive run charged to Castro. Through 13.1 innings, Castro has a 3.38 ERA, 1.50 WHIP, 20:8 K:BB and two holds in 14 appearances. The hard-throwing righty has been reasonably effective in a versatile role, although he's not likely to challenge Edwin Diaz for saves.