Bummer struck out two over a scoreless inning in Saturday's 7-3 win over Cleveland.
The White Sox's bullpen, projected as a strength entering the season, posted a 4.50 ERA and blew seven saves during April. Bummer has not been excluded from the struggles. He told Jared Wyllys of the Chicago Sun-Times that a dropoff in his performance this season is due to a mechanical issue. Bummer's strikeouts are down and walks up thus far in 2021, but he still has a respectable 2.08 ERA over 8.2 innings.