Australian Open: Improving Nadal plays best set yet to down Fognini

Rafael Nadal said he played his best set of the tournament in beating old nemesis Fabio Fognini at the Australian Open Monday as the world number two fights back to fitness from a back injury.

The Spaniard moved into his 43rd Grand Slam quarter-final with his 6-3, 6-4, 6-2 win on Rod Laver Arena, which set up a clash with fifth seed Stefanos Tsitsipas.

Nadal has been struggling with lower back tightness since arriving in Australia, but said he was starting to increase his workload as the problem gets better.

"I played first set, without a doubt, my best level in the tournament," said Nadal, who is chasing his 21st major title and sole ownership of the men's record, which he currently shares with Federer.

"Well, it's normal, too, because I was able to practise for two days in a row. That makes an important difference. My physical condition needs to keep improving, but I think this match helps, too.

"I was not able to practise the proper way for the last 19 days," he added. "But yesterday I started again to increase the amount of work on the practice, and today has been a positive victory with some long points, so that helps for the next match."

Read | Nadal crushes fiery Fognini to reach quarter-finals

It is the 13th time he has made the last eight in Australia, moving to joint third on the all-time list behind Roger Federer (15) and John Newcombe (14).

The result keeps him on track to meet top seed Novak Djokovic in the final, with the Serb, who is carrying an abdominal injury, into his 12th quarter-final after seeing off Milos Raonic on Sunday evening.

Next up for Nadal is Tsitsipas, who earned a walkover when ninth seed Matteo Berrettini pulled out of their fourth-round clash Monday, also with an abdominal strain.

Nadal said he was excited about facing the Greek star, and warned he was starting to feel like his old self again.

"If we compare how I was five days ago and how I am today's situation, it's different, and my perspective and excitement is completely different," he said.

Coming into the clash, Nadal owned a 12-4 advantage over the flamboyant Fognini dating back to 2013 and he looked sharp, but it wasn't vintage tennis from the 34-year-old.

Also Read | Nadal closes in on Slams record with emphatic win

He didn't serve at his best but returned well, creating 19 break point chances although he only converted six.

Nadal raced to a 3-0 lead in the first set after hitting several stunning winners.

But the 33-year-old Italian gathered himself, breaking back before Nadal immediately broke again.

The Italian saved three set points, but his resistance finally crumbled after 46 minutes.

In the second set, Fognini broke for 4-2 when Nadal fluffed a forehand. But Nadal broke back and broke again before wrapping up the set.

He accelerated in the third set and raced to the finish as Fognini faded.