Huff, who started in pole position and needed only a podium finish to wrap up the title, had a heavy brush with the barriers just five laps from the end.
Muller took an early lead with a snappy getaway but Huff stayed close for the first few laps. And while it did not take long for Huff to pass Muller, a sharp corner at speed saw him hit the wall.
Damage to the left-hand side of the Brit’s car forced him into the pits, leaving Muller to shoot ahead and fight off Alain Menu, who stayed on his tail to take second place.
The result reduces Huff's lead on Muller to just 17 points ahead of the final race, with 25 points still up for grabs.
Menu is 19 points shy of Huff, meaning all three Chevrolet drivers are still in with a shot at the title going into the final race.
Alex MacDowall will start from pole position in race two ahead of Pepe Oriola while Menu will sit back in eighth, Muller in ninth and Huff in 10th.