Juan Martin del Potro proved gracious in defeat after Fabio Fognini surprised the world number four to win the Los Cabos Open final in straight sets on Saturday.

Del Potro, the top seed for the ATP 250 event in Baja California Sur, had been aiming for his third tournament victory of the year and his second in Mexico, having already claimed the Mexican Open in March. 

It was not to be for the Argentine, though, Italian Fognini registering an unexpectedly comprehensive 6-4 6-2 victory in the decider.

"It was a good week for me," Del Potro said.

"Unfortunately, I couldn't play my best tennis in the final. But Fabio deserved to win. He played a very smart game. He took all the chances to win, and I think he's a good winner of the tournament. 

"But in many ways I'm looking forward to keep playing better and better in the next tournaments."

Fognini broke Del Potro twice in the opening set and twice in the second, while dropping his own serve just once throughout.

The world number 15 secured the eighth ATP title of his career and third in 2018, having previously won in Brazil and Sweden this year, although it was his first success on hard courts and the first time he has managed more than two tournament triumphs in a calendar year.