That means the agreement will see Day participate in several series this upcoming season.
The 19-year-old will race a part-time schedule in the Xfinity Series, for example, whilst additionally also taking part in the Truck Series, ARCA Menards Series and Trans Am Series.
"What he’s already accomplished at this point in his career speaks volumes, and it’s been impressive to see how quickly he’s adapted to pavement.
"We’re excited to welcome him to our team.”
Additionally, 2021 Cup Series champion Larson, who drives for Hendrick Motorsports, told SiriusXM NASCAR Radio: “Of guys who haven’t made it to the three series in NASCAR yet … he’s definitely the best prospect out there,”
“I definitely endorsed him for sure because I’ve gotten the chance to race with him and firsthand see how good he is.
"He’s probably the only one that I’ve raced with that I feel like looks like me out there. Same sort of driving style and all that, and very versatile and can hop in anything and figure it out.
“I feel like he’s gonna do a great job. When you’re with Hendrick Motorsports, you’re given a great opportunity to showcase your abilities. He’s gonna have a lot of fun this year gaining experience and hopefully he can show the world how good I know he is.”