As the Round of 12 in the NASCAR Cup Series Playoffs nears conclusion on Sunday, NASCAR William Byron is less concerned about the opponents he sees on the race track than the driver he sees in the mirror.

“It’s definitely us against ourselves,” said Byron, who leads the series with six victories, the most recent of which—at Texas Motor Speedway—has propelled him into the Playoffs’ Round of 8.

“I feel like it’s us executing races. It’s us putting together good performances… top five performances that we know that we’re capable of.”

The Texas win allows Byron to concentrate on trying to maintain momentum in Sunday’s Bank of America ROVAL 400 at the Charlotte Motor Speedway Road Course (2 p.m. ET on NBC, PRN and SiriusXM NASCAR Radio).

“For us, it’s definitely going to be less stress,” said Byron, who will start 14^th in the No. 24 Hendrick Motorsports Chevrolet. “But once we get to the race track, we’re trying to win the race, so it’ll be stressful because of that.

“Qualifying here is tough because you can lock up tires and miss corners. There’s a lot of shifting, so it’s tough to get it all right. I feel like you can hit 90 percent of the track right and miss 10 percent, and that can be worth two or three-tenths (of a second).

“Last year, I looked at my qualifying, and I qualified second here. I just missed a little bit in (Turns) 7, 8 and 9, the back chicane, and that was worth two-and-a-half tenths. Had a great lap going up until that point. It’s definitely a tough place.”

Byron finished 16th a year ago but was sixth, sixth and 11th in his three prior starts. He just won at Watkins Glen and was fifth earlier this season in COTA. He was solid in being 14th, 13th, 14th in the other three road races. Byron has scored the most points on road courses (154) this season and has led two races for 94 laps.