“Such a great dude!” Luyendyk Jr., 36, wrote alongside a picture of the pair posing together at the event while wearing matching red and black Honda racing suits.
Continuing, the reality star added that it had been “Fun meeting @channingtatum and getting to lead the field to green in the @Honda IndyCar 🤙🏼.”
As part of his official duties at the event, Tatum let the racers know when it was time to “start their engines” and got to ride in a two-seat Indy car alongside Luyendyk Jr. — but as part of his unofficial duties, he also helped send a special message to the 36-year-old’s fiancée Lauren Burnham, who wasn’t able to attend the race.
After revealing that he was “missing @laurenburnham” and had a “little surprise” for her on his Instagram Story, Luyendyk Jr. shared a video of himself and the 37-year-old movie star.
“What’s up Lauren,” Tatum said in the video while giving her a wave. “I’m about to do something stupid.”
“And wishing you were here, obviously,” Luyendyk Jr. added.
“Yes,” Tatum replied with a little laugh.
Luyendyk Jr. also shared a short video of himself and Tatum getting “distracted by the cars going by” while they appeared to be giving an interview.
“I’m honored to be serving as the grand marshal for the Honda Indy Grand Prix of Alabama,” Tatum said in a press release for the event. “I have always loved the excitement of a great race and it’s a privilege to be back in my home state for this event.”
Tatum’s outing comes just two days after Dewan made her own first public appearance post-split, as she attended the St. Jude Children’s Research Hospital’s fifth annual Hope and Heritage gala to receive the organization’s 2018 research award.
“Thank you @stjude for this incredible honor!” Dewan wrote on Instagram later, captioning a photo of herself and the glass award. “I am so proud of everything you do and continue to do for children.”
A source close to the couple previously told PEOPLE the pair tried to make things work after “growing apart” over the past year.
“They really wanted to make their marriage work,” said the insider. “But neither of them are people who will stay in something that isn’t fully right.”