Jamie Whincup responded to his race three defeat by winning the last race of V8 Supercars' inaugural Austin weekend.
Race three winner Fabian Coulthard put Whincup under huge pressure in the first half of the race. But in the closing laps, Whincup was able to pull out a three-second lead, as he clamed his third win of the weekend and extended his points lead still further.
Prior to Austin, Will Davison had been Whincup's closest championship rival. His title chase received a major blow in Texas though, as he retired after crashing into Scott McLaughlin in a misjudged passing move.
Shane van Gisbergen had a relavtiely quiet run to fourth following a few closer dices early on.
Garth Tander was one of those overtaken by van Gisbergen. He then resisted Craig Lowndes, up from 12th on the grid, and Mark Winterbottom to secure fourth.
Jason Bright, Rick Kelly, Jonathon Webb and James Courtney completed the top 10.