Mathews completed four innings in Game 1 of Monday's doubleheader against Cincinnati, allowing one run on two hits and three walks while striking out seven batters in a no-decision.
Mathews was called up from Triple-A Memphis early Monday and handed the ball for the matinee. The southpaw held his own, allowing just one run on a fourth-inning solo homer by Dane Myers. Mathews racked up 12 whiffs and seven punchouts, though he was a bit wild and needed 95 pitches (55 strikes) to complete only four frames. It was just the second appearance of the 25-year-old's big-league career; in his MLB debut Aug. 1 in Toronto, Mathews yielded three runs over five innings in a loss. Unless St. Louis opts to shift to a six-man rotation, there doesn't seem to be room for Mathews to remain with the big-league club as a starter for now, but he'd likely be a top candidate to move into the rotation should any of the Cardinals' other starters suffer an injury or get demoted.