Zane Smith thought he was coming to the World Wide Technology Raceway to compete in the Camping World Truck Series event until everything changed at 3 p.m. on Thursday.

Chris Buescher cannot compete this weekend for RFK Racing in the No.17 because of a positive COVID test so Smith, a full-time competitor for Ford in the Camping World Truck Series, will substitute for Buescher and make his NASCAR Cup Series debut on Sunday afternoon.

Smith said it’s been “wide-open” since he got the news.

“I’ve just been talking to everybody,” Smith said late Friday after running Cup Series practice and Truck Series practice and qualifying. “The Cup garage, there is so much info that these guys are able to see and so much data. That’s been the biggest difference.

“The truck stuff is quite different from that and obviously, this is the best of the best. You work all your life to get in this garage, and I’m just lucky to be here.”

Smith walked into the Cup Series garage on Friday, where he was fitted for the car and completed a 50-minute practice session without incident. There has been a lot of debriefing and conversations with the team, (driver/co-owner) Brad Keselowski and many others.

“Very” surreal was the best way Smith could describe it.

“It is so weird,” Smith said. “I don’t really know how to word it. I woke up this morning and said, ‘Yeah, it wasn’t a dream.’ Just crazy, crazy.”

Smith repeatedly said he’s trying to make the most of the opportunity and get better with each lap. And because he’s running both races, it’s an adjustment going from his Front Row Motorsports truck (which felt slower after running the Cup car) to the Next Gen car.

“I was definitely a fish out of water for the first bit, just trying to learn as much as I can,” he said. “I was definitely kind of on eggshells, especially with how these cars drive. They’re a lot different than anything I’ve ever driven before.

“I don’t want to be that guy to go full send and tear up one of these cars. It’s a great opportunity for me to learn a lot and that’s my goal.”

A good Sunday afternoon for Smith is completing all the laps.

“Yeah, I can go out there and probably be a couple of tenths quicker and have a good chance of wrecking,” he said. “These cars are not forgiving at all, and you don’t want to overstep that threshold. I don’t want to throw this opportunity away when there’s a big chance to learn a lot on Sunday.”

Smith has 56 starts in the Truck Series and six wins, three of which have been this season. He’s also made 11 starts in the Xfinity Series.

So how is it that he got the call to fill a Cup Series seat?

“I don’t know,” he said. “That’s a good question. I had gotten a text earlier in the day from Brad saying, ‘Hey, congrats on the wins. Looking good.’ It was around those words, which was really cool, but you don’t get that from guys in this garage.

“I didn’t even think about it. I was like, ‘Oh that’s cool.’ And then, later on, I got a call from him and had seen a few tweets of his opinion on me. That’s just so awesome to hear.

“I’m really in a lot of disbelief. I’m not a type of guy [who goes], oh man, I deserve this. I truly don’t belong here. We came from literally nothing, and I worked all my life to get here, and it’s about been taken from me multiple, multiple times. So to have this opportunity means everything.”