With Austin Dillon the top rookie in the Nationwide Series and younger brother Ty making his presence felt in his first year in the Camping World Truck Series, the only competition between the two grandsons of Richard Childress these days is for bragging rights in the family.

The sibling rivalry wasn't supposed to extend to the race track. Not yet, anyway. But circumstance, opportunity and a little bit of pleading have led to Ty Dillon's unexpected debut in the No. 33 Nationwide race car on Saturday at Dover International Speedway. He joins his brother, Austin, who races the No. 3 Chevrolet for Richard Childress Racing, in what will be a cowboy hat Dillon double at Dover.

Ty Dillon is replacing Brendan Gaughan, who is committed to an off-road event this weekend. Kevin Harvick was next in line for the ride, but he was already set to run the Truck race on Friday in addition to Sunday's Sprint Cup race and didn't want to compete in three races in three days at Dover.

"So I was there at the shop and they were trying to find somebody to drive and I was like, 'Hey give me a shot. I'm ready. I want to do it,' " Ty Dillon said. "And luckily Brendan and everybody at [sponsor] South Point believed in me, Kevin believed in me, a lot of guys at the shop did, so very thankful for the opportunity to get it this soon and in this fashion and to make my first start at Dover."

Ty Dillon, the ARCA champion last year, has been the top rookie in the Truck Series this season. He entered Friday's race third in the standings, behind Justin Lofton and Timothy Peters, with five top-10 finishes in his first five races.

Dillon said he felt right at home on the track during his first practice on Thursday.

"There's not much close to it,' he said. "Maybe a dirt car around Eldora or around some of the short tracks we run on dirt. It's so wide open, so fast around this place. It's almost hard for your eyes to adjust sometimes going off into the corner. It's super exciting. It's my style of racing. I've grown up on the dirt tracks and faster style cars, dirt late models ... so not much similar in the cars, but the speed and the thrill that you get from going around a place like this is very similar. So I felt right at home first couple of laps."

Dillon qualified sixth for Friday's Truck race, which remains his focus for the weekend. He already has received some advice from his older brother, who is third in the standings and the top Nationwide rookie going into this weekend.

"I talked to him a little bit about it,' Austin Dillon said. "He's really excited, so I think he'll be fine. He's got a great team with [crew chief] Ernie Cope and the No. 33 boys. So actually, he'll have more experience here than we've had at times in the past. He's gotten to run the trucks beforehand, so he should be up to speed in the Nationwide car.

"Hopefully I never lap him and hopefully I never see him come by me. Hopefully he stays behind me and has a good day."

Ty Dillon said he will race his brother carefully. For now.

"He's my brother so he gives me everything that I ask for,' he said. "He's a wonderful teammate and a wonderful person to me. He's always there to see me do well. If there's anything I can help him with as far as what I'm doing I'll help him. We are super competitive against each other. Don't get me wrong. We always want to beat the other one, but we also want each other to win and succeed in what we're doing.

"Eventually it's going to come down hopefully to where we're racing each other every week in the top levels of NASCAR and hopefully we'll be able to push each other to be 1-2 and put RCR back on top of the world in racing."