Mark Wahlberg Rides with Blake Koch at Drive4Clots 300!

Mark Wahlberg keeps it cool and casual as he poses alongside NASCAR driver Blake Koch while attending the Drive4Clots.com 300 held at the Auto Club Speedway on Saturday (March 21) in Fontana, Calif.

The 43-year-old actor was there in support of Blake, 29, who drove the No. 8 AQUAhydrate Toyota in partnership with the performance water brand, which Mark is an ambassador for.

PHOTOS: Check out the latest pics of Mark Wahlberg

The week before, Mark was spotted showing off his muscular body at the pool with his wife Rhea Durham during their vacation in Cabo San Lucas – Check out the shirtless pics here!

FYI: Mark is wearing Timberland shoes.