Rookie mistake took Connor Zilisch out of contention at Las Vegas

A poised Connor Zilisch ran one of the most impressive races of his young NASCAR career at Las Vegas Motor Speedway on Saturday. 

The 18-year-old Xfinity Series rookie looked like a rookie during one of the race's most crucial stints — a rare occurrence for a young driver who's wise beyond his years. 

After pacing the field in practice and qualifying third, Zilisch finished fourth in Stage 1 and third in Stage 2 to set himself up for a run at the race win in Stage 3. 

On Lap 100, Zilisch marked the halfway point of the race by making a bold move on the outside of Aric Almirola to take the race lead. 

Zilisch's run at Las Vegas on Saturday was arguably his most impressive performance on an oval so far in his Xfinity Series career, and he led 28 circuits in total. 

While JRM teammate Justin Allgaier eventually overtook Zilisch for the lead, the rookie still had a top-five finish — at the least — well in his sights. 

That was until Lap 146, when Zilisch brought his No. 88 Chevrolet down pit road for the final time during a round of green flag pit stops. After making his stop, Zilisch was penalized by NASCAR for speeding on pit road, incurring a costly pass-through penalty. 

A strung out field meant Zilisch didn't lose as many positions as he could've had the incident taken place at a different track, but any hope of a race win or a top-five was wiped away in an instant.