The Tigers designated Lucas for assignment Friday, Evan Petzold of the Detroit Free Press reports.
Lucas will lose his spot on the 40-man roster with the Tigers selecting the contracts of Jace Jung and Trey Sweeney. Lucas hasn't pitched for Detroit since July 28. The 27-year-old has a 10.29 ERA in MLB this season but posted a 3.51 ERA across 33.1 innings with Triple-A Toledo, where he'll likely remain if he goes unclaimed on waivers.