Yamamoto (2-0) picked up the win Tuesday, scattering two hits and two walks over seven scoreless innings while striking out seven in a 6-0 victory over the Cardinals.
St. Louis hitters had even less success against Yamamoto in their second look at him than they did in his debut -- a ground-rule double by opposing pitcher Jack Flaherty marked the only time the Cards even got a runner into scoring position against the 23-year-old. Yamamoto is quickly locking down a permanent rotation spot for Miami, but he'll face a tough test in his next start Sunday in Philadelphia.