After struggling in a brief Triple-A stint last year, Lyles opened the Oklahoma City RedHawks' season in less-than-stellar fashion Thursday, surrendering three runs over four innings against the Memphis Redbirds.
MLB.com's No. 31 prospect gave up seven hits and issued two walks while striking out one.
While Lyles' start was far from ideal, his counterpart had an even rougher night. Memphis' P.J. Walters also lasted only four innings and was charged with five runs on six hits and a pair of walks.
The RedHawks held on for an 8-7 victory in their first game as the Astros' Triple-A affiliate, holding off a late comeback by the Redbirds.
Lyles' offense spotted him two runs in the top of the first, but the 20-year-old right-hander gave one back in the bottom of the frame as Shane Robinson scored on Peter Kozma's sacrifice fly.
Lyles settled down and pitched two scoreless frames before running into trouble again in the fourth, when Robinson smacked a two-out two-run double. Lyles again induced an inning-ending groundout, but his evening was over after 81 pitches.
Robinson finished 5-for-6 with three RBIs and two runs scored. Oklahoma City employed a more balanced attack as six RedHawks drove in runs.
Walters (0-1) took the loss, while Major League veteran Gustavo Chacin (1-0) tossed a scoreless inning for the victory.