Gagne and Petrucci went to the Alabama track split by just four points at the head of the standings, but a 12th win of the season in Saturday's opener and a second-place finish in Sunday's curtain-closer proved enough for the American rider was enough to defend his crown.
Warhorse HSBK Ducati rider Petrucci on the other hand finished fourth in the first race after being handed a five-second penalty for jumping a start, although this was subsequently overturned, promoting him to third.
