The veteran Karl, competing in what are expected to be his final Games, was trailing for much of the final in Livigno but crossed the line 0.19 seconds in front of his rival.

Bulgaria's Tervel Zamfirov took bronze.

Karl, 40, celebrated his victory by stripping to the waist and letting out a huge roar before lying face down on the snow.

He has one Olympic silver from Vancouver 2010, a bronze from Sochi 2014, and he won gold at the Beijing Games four years ago.