AUSTIN, Texas – Thursday at Circuit of the Americas, three-time NASCAR Cup Series champion Tony Stewart returned to a stock car for the first time since retiring from NASCAR competition at the end of the 2016 season.

Nov. 20, 2016 when he retired as a NASCAR driver following the season-ending Ford EcoBoost 400 NASCAR Cup Series race at Homestead-Miami Speedway.

Stewart strapped back into his No. 14 Haas Automation Ford Mustang from Stewart-Haas Racing and made a demonstration run at the 3.426-mile, 20-turn track in advance of this weekend’s United States Grand Prix.

Unlike any other time he drove in the NASCAR Cup Series in a career spanning 18 years, Stewart’s Ford Mustang was outfitted with a passenger seat as he showed Haas F1 Team drivers Romain Grosjean and Kevin Magnussen how to wheel a 3,200-pound race car around America’s only purpose-built Formula One venue.

“It was a lot of fun to come to a venue that we’ve never been to, but provide an opportunity for Romain and Kevin to get in the car and make laps at a venue they’re comfortable with and familiar with, but in a different kind of car,” Stewart said. “For me, it was a car I’m familiar with, but a venue I wasn’t familiar with. It was lot of fun for me to get in our Haas Automation Ford Mustang and run here, but a lot of fun for me to watch those guys and see how much they enjoyed driving the car.”

For Grosjean and Magnussen, it was a rare moment to drive a race car that is the polar opposite of what they drive in the FIA Formula One World Championship.

“It’s been the best Thursday of the year, by far,” said Grosjean, whose most applicable stock-car experience had been when he piloted a Ford GT1 in the 2010 FIA GT1 championship. “Tony Stewart giving you a ride in a NASCAR stock car is already something very unique, and then having the chance to drive it is pretty special. Kevin and I really enjoyed ourselves. We gave it some cheese and smoke at the end. It was just fun to discover something that’s very different, yet very much the same as far as the way you drive it and the way you feel the car.

“The gearbox was really good. I was not expecting such a good gearbox. A bit long off the line, and it worked for the burnouts. A really good engine with really, really good sound. It’s a heavy car, but it’s quite a drive and I was happily surprised by it.”

Magnussen’s experience was even more limited. Prior to Thursday, the only time he had wheeled a race car with a roof and fenders was when he sampled a GT2 car and a DTM car. However, this was the second time Magnussen received driving instruction from Stewart. Stewart taught Magnussen how to pilot a 1,350-pound sprint car with 750 horsepower last October at Carolina Speedway in Gastonia, N.C.

“It was awesome,” Magnussen said. “Always wanted to drive a NASCAR stock car and it was great to have Tony there, once again, driving one of his cars. I drove his sprint car last year and he was there for that and instructed me. That was a great day, too. Again, really good fun and a bit of a dream come true to drive one of those iconic cars. It’s a big ol’ racecar. It’s moving around a lot more and it doesn’t really have any downforce and it’s very heavy. It’s a carbureted engine and the throttle response is pretty different. There’s something very raw about it. It’s very old-school and, what can I say, it’s just a bad-ass racecar.”

Stewart was impressed by how quickly Grosjean and Magnussen acclimated themselves to his No. 14 Haas Automation Ford Mustang.

“I’ll go back to what we did a year ago with Kevin Magnussen. We took him to a track in North Carolina and took our 360 winged sprint car and he ran about 40 laps and, at the end of 40 laps, we had him within four tenths of what I ran in the same car,” Stewart said. “Days like that and days like today provide the opportunity to see how elite drivers are truly that – elite. We put Kevin and Romain in a car that they’ve never been in before, and they went out and had a lot of fun and ran some pretty competitive lap times. It just shows why these guys got their opportunities in Formula One, and why they have that talent to do it. They just have that natural ability to drive a race car.”