In the return to COTA for the NASCAR Cup Series’ third event at the 20-turn circuit, Brad Keselowski’s day ended prematurely due to a mechanical failure. He finished 35th.

NASCAR’s newest road course rules were on display Sunday for the first time as stage breaks are eliminated, with stage points being awarded at the scheduled lap end of each stage under green-flag conditions. Keselowski worked his way up to 21st by the end of the opening stage of 15 laps that saw a pair of caution flags early, the first resulting from a spin by the No. 6.

Stage two ran all green as Keselowski finished 28th. He again powered his way into the top-20, advancing to 19th at lap 48 with 20 to go. Then, with 11 to go, his Ford Mustang came to a rest on the track as a mechanical failure sent him to the garage for the afternoon.

The No. 6 team returns to action next week at Richmond Raceway. Race coverage Sunday is set for 3:30 p.m. on FOX. Radio coverage can be heard on MRN and SiriusXM Channel 90.