Siem and McKibbin finished at 10-under overall and then the German birdied the opening play-off hole to seal it. It was his sixth victory on the DP World Tour.

Siem was three strokes ahead of clubhouse leader McKibbin eight holes into his final round. Then four bogeys put him one stroke back going to the 18th. But Siem holed a 22ft putt to finish with an even-par 71 and force the play-off.

"Holing that putt on 18 was one (of) the coolest moments in golf for me and doing it again in a play-off was fantastic," Siem said.

McKibbin posted a bogey-free 65 in his final round at Adriatic Golf Club Cervia.

McKibbin had the consolation prize of earning a spot in the Open Championship along with American Sean Crocker, who finished one stroke behind the leaders in a tie for third with Jannik de Bruyn.

Siem, 43, won his first European tour title more than 20 years ago. He lost his tour card in 2021 and won it back at qualifying school last year. Then he won the Indian Open at the start of last year for his first tour victory in more than eight years.

Australian David Micheluzzi had a final-round 70 to finish seven-under in a tie for 10th place.