NEW YORK -- The Astros are preparing to call up right-hander Jordan Lyles and left-hander Dallas Keuchel from Triple-A Oklahoma City, a baseball source told MLB.com on Tuesday.
It's unknown what the corresponding roster moves will be, but the Astros have yet to announce who will start Thursday's game against the Tigers in Houston. That's the rotation spot formerly occupied by Brad Peacock, who struggled and was moved to the bullpen.
Astros general manager Jeff Luhnow couldn't be reached for comment.
Lyles, 22, was set to begin the season in the Astros' starting rotation, but he was sent to Triple-A following a poor spring. He went 2-2 with a 5.32 ERA in six games (five starts) for the RedHawks, throwing a strong game on Saturday in which he allowed three hits and one run in five innings.
Lyles made 25 starts for the Astros last year and went 5-12 with a 5.09 ERA.
Keuchel, 25, also began the season in Oklahoma City but was recalled on April 6 when Travis Blackley went on the disabled list with a left shoulder strain. Keuchel posted a 3.38 ERA in 10 2/3 innings spanning four relief appearances with Houston before being sent back down on April 21 when the Astros' bullpen was in need of a fresh arm.
Brian McTaggart is a reporter for MLB.com and writes an MLBlog, Tag's Lines. Follow @brianmctaggart on Twitter. This story was not subject to the approval of Major League Baseball or its clubs.