Lucas Luhr and Klaus Graf rolled to their fifth consecutive American Le Mans Series victory on Sunday at Road America, holding on after a strong challenge by the revolutionary DeltaWing to take another victory.

The DeltaWing had led in the series for the first time in tricky conditions but ultimately it was the championship leaders who emerged on top of the pile when the chequered flag dropped.

Luhr extended his ALMS-leading total to 46 victories, while Graf won for the 19th time.

"I don't remember the last time we drove in the rain, and it was tricky in the beginning because no one drove here this weekend in the wet," Luhr said. "As the track got better and better, it was in our favour.

The Muscle Milk Pickett Racing recap from the weekend can be viewed below...