Rafael Nadal says he was pleased with the manner of his win over John Isner as he booked his spot in the China Open semi-finals.

Nadal hails 'important' victory

Nadal hails 'important' victory

The top seed had to cope with an eye problem during the quarter-final contest but managed to overcome it to record a 6-4 7-6 (7-0) straight sets triumph to remain on course for a sixth title in Beijing.

The world No.1 secured a vital break at 5-4 in the first set before holding off a resurgent Isner in the second to secure his place in the last four via a tie-break.

Big-serving American Isner had impressed in his first appearance since the US Open and Nadal was therefore delighted to overcome him.

"I think I played a solid match," Nadal said. "I played very well, changing good directions... I think on return I did well.

"It's an important victory for me, of course, against a player that arrived here playing so well, winning two great matches. For me it's an important one and I'm very happy."

Awaiting him in the semi-finals will be Bulgarian third seed Grigor Dimitrov after he defeated Spain's Roberto Bautista Agut 7-6(5) 4-6 6-2.

In the other last four encounter, Nick Kyrgios will face second seed Alexander Zverev, Kyrgios having been a set and 3-0 up before his opponent Steve Darcis retired hurt. Zverev, meanwhile, ousted Russian teenager Andrey Rublev 6-2 6-3.