From BA:

Welch is a compact, yet physical 6-foot, 200-pound righthander who posted a 4.65 ERA with 88 strikeouts to 24 walks across 89 innings this spring. An advanced strike-thrower, Welch has a five-pitch mix that includes a low-90s fastball, a high-80s cutter, a low-80s slider, a mid-70s curveball and a seldom-used low-80s changeup. Both his slider and cutter this spring generated whiff rates north of 30%, and he projects as a back end, innings-eating starter.