Lyles was optioned to Triple-A Albuquerque on Tuesday, Patrick Saunders of the Denver Post reports.
Lyles has started five games during his in the majors in 2016, earning a dismal 8.55 ERA and 2.05 WHIP over 20 innings pitched. He was sent down to the minors when Jorge De La Rosa (groin) was reinstated Tuesday to make his first start since injury against the Red Sox. Lyles will spend some time in Triple-A making adjustments, but he could be called up again later in the year if he's needed.