In 2010, Vision Racing lost its sponsors and as a result shut down as a full-time team. Therefore, Carpenter drove for Panther Racing in conjunction with Vision Racing in the No. 20 Dallara-Honda at the Indianapolis 500. In the race, Carpenter started in 8th place and finished in 17th place due to a caution occurring during a round of pit stops, which put Carpenter a lap down. The two teams later fielded the car in the Peak Antifreeze & Motor Oil Indy 300 at Chicagoland, the Kentucky Indy 300 at Kentucky and the season-ending Cafés do Brasil Indy 300 at Homestead. At Chicagoland, Carpenter started in 11th place and quickly challenged for the lead, leading for 3 laps. Carpenter then had handling issues and retired with around 20 laps to go; he was scored in 20th place. At Kentucky, Carpenter qualified on pole and led a front-row sweep with teammate Dan Wheldon. Carpenter led for 11 laps and almost achieved his first victory when cars ahead of him had to make pit stops late in the race; he ultimately finished in 2nd place as Hélio Castroneves managed to conserve fuel to the end of the race without making another pit stop. At the season-ending race at Homestead, Carpenter started in 7th place and finished in 13th place, one lap down. Carpenter finished in 28th place in the drivers' championship with 90 points.