'Don't do it again': Fans erupt over Nick Kyrgios act at Miami Open

Nick Kyrgios has continued his stellar form at the Miami Open, taking down 30th seed Fabio Fognini on his way to the fourth round.

The Aussie star beat his veteran opponent - ranked 34th in the world - 6-2 6-4 in just 61 minutes on Sunday.

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The Italian looked to be out of sorts in the opening set and struggled with his movement.

Kyrgios took full advantage of his opponent's woes and won the set in 28 minutes, breaking in the opening game and again in the seventh.

Fognini rallied in the second set but had no answer as Kyrgios played with confidence and guile.

Serving at 2-3, Kyrgios hit an underarm serve after a fan in the stands yelled out and asked for one.

The serve ended up being a fault but both Kyrgios and Fognini seemed to see the funny side, with the Italian appearing to say "don't do it again" with a smirk.

The Australian, eight years younger than Fognini at 26 but ranked 102nd, looked frustrated at this inconsistency as the match went with serve to 4-4.

But Kyrgios then stepped up his level of play, winning eight points in a row to break Fognini before serving out the victory.

“We all know that we have a bit of a dual personality problem out there, me and Fabio, so I knew today I had to really lock in and let him do the double act type thing,” Kyrgios told the Tennis Channel.

“I knew that if I came out with some energy and jumped on him early, I was going to run with it.

“They way I’ve played the last couple of matches, I can’t really ask for much more.”

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British commentator and former Wimbledon finalist Tim Henman said of Kyrgios: "It was a really great performance, not only was his tennis of a really high standard I thought mentally he kept his composure really well.

"It was mature, professional, calculated.

"He'll be extremely pleased with his progress so far."

Kyrgios advanced to the showdown with Fognini after upstaging World No.7 Andrey Rublev in the second round.

Kyrgios needed just 51 minutes to stun the Russian star 6-3 6-0 to continue his remarkable run of form.

The Aussie advanced to the quarter-finals at Indian Wells last week before going down to Rafa Nadal.

"I don't think I played unbelievable, I just played the right way," Kyrgios told Tennis Channel.

"Against Rublev, you know he wants to try and dictate, to have a lot of rhythm, and I didn't give him that today.

"I tried to slap as many winners as I could, serve well and get up the court on my return and it worked."

The win will see Kyrgios rise further from his world ranking of 102 and came immediately after he was handed a $25,000 ($AU33,000) fine for almost hitting a ball boy with his smashed racquet at Indian Wells.

with AAP

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