Grigor Dimitrov holds off Nick Kyrgios in enthralling fourth-round match

Dimitrov proved king of the tie-break to win 7-6, 7-6, 4-6, 7-6 and showed how hard it will be for the British No 2 when they meet in the quarter-finals.

The third seed said: "Playing against Nick is always tricky".

"Maybe a few things I could do better, and I will try and do that when I play him". He was serving unbelievable, playing unbelievable, competing. He deserves a lot of credit. "You never know when you're going to get an opportunity".

"It was a close first set and I didn't feel I got the best start", he said. Dimitrov takes on Briton Kyle Edmund next. Dimitrov went 3/1 ahead, but Kyrgios rallied to level at 4/4 before Dimitrov raised his game once more at the vital moment to take a firm hold of the match with a two-set lead.

"But then after that it was just impossible. everything kind of slipped away from me". It was a very good match.

Kyrgios appears to have largely won over a sceptical Australian public with his professional attitude this tournament, focusing throughout matches and showing that he does care about tennis after all. Clinical winners on the forehand and up at the net brought up three match points and the second was taken by Dimitrov courtesy of an emphatic forehand, cross-court passing shot victor. Once again, the two-time Grand Slam semi-finalist would prevail.

'I think sometimes he misses confidence.

He needed to step up to have a chance against Kyrgios, and he did, showing the all-court talents that once saw him labelled as Roger Federer's natural successor. That basic error did not prove immediately costly as Dimitrov wilted with the finish line in sight and Kyrgios sent a backhand victor up the line to hit back.

But Dimitrov got a crucial service break in the eighth game of the fourth set when Kyrgios put a smash into the net to allow the Bulgarian to serve out for the match. A well-placed volley handed Dimitrov the advantage in the tie-break, which he built upon as Kyrgios went long and the Australian's double-fault handed his opponent the opening set.

Edmund duly delivered with 23 unforced errors as Seppi, a decade older and a veteran of three previous trips to the fourth round of the Australian Open, held serve easily and mustered up five break points.