CONCORD, N.C. – Early in last Sunday’s race at ISM Raceway, William Byron didn’t look to be in contention with the leaders.

After starting 11th, he slid back in the pack but maintained his top-20 position for the first stage-and-a-half. Then, No. 24 team crew chief Darian Grubb made the call to take two tires on pit road when most competitors elected for four.

That changed Byron’s day, putting him inside the top 10 for the first time.

“I think the two tires worked for us, just the way our car was handling, we were really tight all day and we couldn’t really get that out of it,” the driver explained. “But, the middle stage of the race we started running closer to the top 10, ninth or 10th I think, and that was the perfect call at the time.”

He managed to hold on to the top-10 position for much of the next portion of the race, but he still wasn’t part of the group battling for the lead. That is, until Grubb made another two-tire call during a caution early in the final segment.

“I was a little, I guess, not sure if it was going to work out just because we had done it already one time,” Byron acknowledged. “But, it worked out, we could kind of keep some clean air and I think that was a net gain for sure.”

The gamble put Byron in the race lead for the first time in his NASCAR Cup Series career, and he held it to pace the field for 15 laps before losing the lead to competitors with four fresh tires.

It made him the third-youngest driver to lead 15 or more laps in Cup Series history and the second-youngest to lead laps at ISM Raceway. Overall, he is the eighth-youngest driver to lead a lap in Cup Series history – and four of the youngest eight have driven for Hendrick Motorsports.

“I think it just showed myself that I can do it that I can do those restarts up there,” Byron said. “I know I have the pace up there to run until our handling kind of took over.”

In the end, he earned his best Cup finish to date, and was the top-finishing rookie, taking the checkered flag in 12th.

“I felt like if we can really start to hone in on what we need a little better, we are going to be right there,” he said. “It’s going to take a little bit of work, but it was fun to at least be up there a little bit.”