Third seed Milos Raonic through in four sets against Roberto Bautista Agut

The Canadian is now the highest ranked player left in the men’s draw after the shock exits of Novak Djokovic and Andy Murray and will play the winner of the late match between Rafael Nadal and Gael Monfils in the last eight.

"I guess there's always that sort of match where you sort of fall off," Raonic told reporters.

"It's a long two weeks. So I guess unfortunately that was it for me today. So I'm happy I was able to solve that."

Spain's Bautista Agut is the 13th seed but had no answer to Raonic in the final two sets as the big server showed his class on Hisense Arena.

Teak tough Bautista Agut is nothing if not a fighter but Raonic, who said he had been suffering from a fever after his third-round match, raced away with the fourth set to seal the victory with a forehand winner down the line.

"I still don't necessarily feel at full capacity," he added. "I have energy now. I can go about my days normally. Sort of on the tail end of the recovery."

It was not all plain sailing for the 26-year-old, though, who fired down 33 aces and 75 winners in the two hour, 52 minute contest: Raonic was 5-1 down in the first set tie-break before winning 8-6 and then lost the second set.