The Cardinals recalled Mathews from Triple-A Memphis on Monday.
Mathews will start the first game of Monday's doubleheader in Cincinnati versus the Reds. He'll be making his second MLB start, after yielding two runs with a 3:3 K:BB over five innings in his debut in Toronto earlier this month. In 21 starts for Memphis this season, Mathews has collected a 3.27 ERA and 120:61 K:BB across 99 innings. He will likely be sent back down following Monday's spot start.