The 6'6" right-hander went the distance for the first time this season, blanking Chicago on five hits, with one walk and seven Ks.
Masterson has allowed just 10 hits and one earned run in 22 innings, holding hitters to a combined .141 batting average, while earning all but one of Cleveland's early season wins (4-5).
In his sixth major league season, Masterson has thrown five complete games. The win over the White Sox was his second career shutout.
Th eonly run of the game came with two outs in the bottom of the ninth, when Nick Swisher singled home Michael Bourn, who had doubled off Chicago reliever, Jesse Crain.
Milwaukee's leadoff hitter, Norichika Aoki, started the game with a single off Cardinals' rookie starter, Shelby Miller, but that turned out to be the only hit the Brewers would get until the ninth inning, as Miller set down 21 of the next 22 batters for seven shutout innings, his only mistake the plunking of Alex Gonzalez with one out in the second.
Trevor Rosenthal worked a hitless eighth, and Mitchell Boggs finished up with his second save of the season, giving up an uneventful single to Jean Segura in the ninth.
Miller threw 113 pitches, 87 of them for strikes as he improved to 2-0. He struck out eight without giving up a walk.
The Cardinals and Brewers go at it again on Saturday at 4:15 pm EDT in St. Louis.