Rockies pitcher Jordan Lyles was at his best Thursday, retiring all 12 of the batters he faced in four perfect innings against the Royals.

Lyles was able to get eight groundouts and two strikeouts during his two innings of work, continuing an impressive spring that has featured just one earned run and three hits allowed in 11 innings as he hones his split-finger changeup.

"I just have a lot of confidence in my changeup, a pitch I haven't had in previous years," Lyles said after the outing, per MLB.com. "It's another pitch I can lead on. I threw it a lot during the game but they haven't been hit hard."

Lyles is looking to improve on a 2014 season in which he went 7-4 with a 4.33 ERA and 90:46 K:BB ratio in 126 2/3 innings.