Cabrera Bello shot a two under par 69 in Sunday's final round to finish tied at 19 under par for the tournament with Arnaus, who closed with a four-under 67 and fell just short of his first European Tour victory.

It was the fourth European Tour win for Cabrera Bello, and his first since the 2017 Scottish Open.

The 37-year-old Spaniard was second to Rahm in the last edition of the Spanish Open in 2019, with last year's tournament cancelled because of the coronavirus pandemic.

"I knew it was going to be a really hard battle today," Cabrera Bello said.

"I've been believing in myself and I've had an amazing support all this week. I was just hanging in there and I knew I would have an opportunity and I'm glad luck fell my way."

RIGHT: Rafa Cabrera Bello celebrates holing the victory putt and claiming his first Spanish Open. PHOTO: Getty Images.  

The last Spaniard to win in Spain other than Rahm was Miguel Angel Jimenez in 2014, with Cabrera Bello now the 13th Spaniard to win on home soil.

Rahm, the two-time defending champion, couldn't make a move in the final round and shot 69 that left him in a disappointing tie for 17th on 13 under overall at the Club de Campo Villa de Madrid.

The U.S. Open champion had started the day six shots off the lead and finished the same distance back.

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Three players ended two shots off the lead – Frenchman Julien Guerrier (69), India's Shubhankar Sharma (66) and Scotland's Grant Forrest (65), who had a hole-in-one in the first round and finished with five birdies and an eagle on his last seven holes on Sunday.

Arnaus and Cabrera Bello were tied for the lead entering the last three holes and both had errant shots off the tee on the 18th.

Cabrera Bello saved par from the greenside bunker, while Arnaus hit it close with his approach but missed the birdie putt that would have given him the win.

Adri Arnaus congratulates Cabrera Bello on his win. PHOTO: Getty Images.

Both missed the fairway again on the 18th in the playoff, but Cabrera Bello went closer and rolled in his putt for the victory.

Wilco Nienaber of South Africa had the best round of the day with a seven-under 64 to finish in a tie for sixth, while Australia's top finisher was Min Woo Lee, whose final round 69 saw him end on nine under in joint-39th place.

Fellow West Australian Jason Scrivener was joint 56th on six under after also shooting two under for his final round.