Kauto Star has triumphed in the Betfair Chase at Haydock Park to cool rumours of his retirement after a disappointing 2011.
The 2007 and 2009 Cheltenham Gold Cup winner went off at 6-1 and came home ahead of this year's Gold Cup victor Long Run (6-5).
Ruby Walsh guided the 11-year-old to victory by eight lengths.
Trainer Paul Nicholls described the victory as the "best day day [he's] ever had".