Zeuch, a 2016 first-round draft pick who made his MLB debut with Toronto last season, worked 1 1/3 innings and allowed solo homers to Gregory Polanco and Lolo Sanchez and a two-run shot to Oneil Cruz.
Off-season acquisition Chase Anderson started the game for the Blue Jays, allowing four runs, three hits and three walks over 2/3 of an inning.
Toronto’s top prospect Nate Pearson pitched two innings in relief, striking out three.
Joe Musgrove earned the win for Pittsburgh. He allowed two runs, struck out two and walked two in three innings.