Stanek, who was called up from Triple-A Durham on Monday, recently developed a splitter to go along with his 100 mph fastball, Bill Chastain of MLB.com reports.
The 26-year-old right-hander worked on the pitch with Durham pitching coach Kyle Snyder over the last several weeks before being summoned, choosing to focus on the splitter as opposed to the slider that he'd previously utilized. While he'd also played around with the splitter last offseason and in spring training, he didn't hone in on perfecting it until returning to Durham following a rough initial major-league stint earlier this season. Stanek has been mowing down hitters with the Bulls, compiling a 47:14 K:BB over 35.2 innings.