Kenseth led the final 41 laps on old tires after opting to only refuel on his last pit stop, then held off a hard-charging Kasey Kahne down the stretch to record his 25th career Sprint Cup Series victory.
It was his first, however, as a member of Joe Gibbs Racing, coming in his third start for the No. 20 team after 13 years with Roush Fenway Racing.
Kahne led for 114 laps but finished 0.6 seconds behind Kenseth.
Defending Sprint Cup champ Brad Keselowski, who also opted not to change tires on his final pit stop, settled for third place.