Playing like there's no tomorrow, Lleyton Hewitt says he's savouring every second of his vintage run at the US Open.
Twelve long years after landing the first of his two grand slam titles in New York, Hewitt will take on unheralded Russian Evgeny Donskoy on Sunday (Monday AEST) for a surprise spot in the last 16 at Flushing Meadows.
The 32-year-old admitted he had to pinch himself after eliminating sixth-seeded 2009 champion Juan Martin del Potro in the biggest shock of the tournament.
His fighting five-set comeback victory was his first over a top-10 rival in New York since beating the great Pete Sampras in the 2001 final.
"For me, I love being out in that atmosphere, sucking up every second of it," Hewitt said.
"I don't know how many years I've got left in me. I keep getting asked the question, so I was just hanging to get out here and play on this court again and try to put on a great show."
He put on such a great show under the bright lights of Arthur Ashe Stadium that del Potro - who grew up in Argentina idolising Hewitt - is tipping the former world No.1 to go even deeper in the tournament.
"He played like he has a chance to go far in this tournament," del Potro said.
"He's a great champion and a great fighter."
Even title favourite Rafael Nadal said he was in awe of Hewitt's fighting spirit, but the man himself is refusing to get carried away.
As the years roll on, Hewitt is finding it more and more difficult to back up big wins at the majors and is wary of Donskoy, likening the world No.102 to Russia's former top-four star Nikolay Davydenko.
"We practised together the day before my first round match," Hewitt said.
"Yeah, his coach just came up and asked. I didn't really know the guy at all. It was only because we both had Wednesday starts that we hit together.
"He's a typical sort of Russian/Czech kind of player - good double-handed backhand. Very good across the baseline with both his groundstrokes. Hits the ball pretty flat. He's a Davydenko kind of player.
"He's not going to be easy by any means. I think he beat (Mikhail) Youzhny at the Aussie Open this year and had some decent wins."
Hewitt eliminated the 10th-ranked Stanislas Wawrinka in another grand slam boilover at Wimbledon two months ago only to slip up in the next round against world No.189 Dustin Brown.
He knows getting his battered body to back up and not having a mental letdown will be critical against Donskoy, who is into the third round of a major for the first time.
"Obviously it's different, not getting up for probably a featured night match on centre court," Hewitt said.
"But it's still staying in the moment and getting another opportunity to try to make the fourth round here.
"That's all I'll be looking at. I'll be doing absolutely everything in my power to prepare as well as possible."
Victory over Donskoy would earn Hewitt a fourth-round clash with German 12th seed Tommy Haas or 23rd-seeded Youzhny for a likely quarter-final crack at world No.1 Novak Djokovic.
