IT is the re-match American tennis has been waiting for: the young pretender against the queen of the court.

Sloane Stephens and Serena Williams will lock horns in the US Open fourth round today in an encounter which takes place against a backdrop of rivalry and retribution.

The 20-year-old's defeat of the 16-time Grand Slam winner in the quarter-finals of the Australian Open was impressive, but her criticism of Williams in a magazine article published in the aftermath, in which she accused the older woman of being unfriendly and ignoring her, lit a fuse.

Both insist any animosity is behind them and that may have a modicum of truth in it but, make no mistake, Williams will be desperate to wipe that million dollar smile off Stephens' face today.

The No 15 seed is one of only three women to beat the defending US Open champion this year.

Although Victoria Azarenka had to come back from a set down to overcome Alize Cornet of France 6-7 (2), 6-3, 6-2 yesterday, the Belarusian has provided Williams with stern competition in the last 18 months and Poland's Agnieszka Radwanska has also been a threat.

Yet America craves a home rivalry, and the one between Williams and Stephens is a marketing man's dream.

Williams, who eased past Kazakhstan's Yaroslava Shvedova, 6-3, 6-1 late on Friday night and who has dropped just a paltry eight games in three rounds, said however: "I don't know if she's my rival. I mean anyone that's playing tennis and that's doing as well as her, you can definitely say that."

In the magazine interview, Stephens claimed Williams unfollowed her on Twitter and deleted her from BlackBerry Messenger in the wake of the Melbourne defeat.

But after seeing off her fellow American Jamie Hampton to seal her path into the fourth round at Flushing Meadows, Stephens played down their differences.

"That's all old news now, and we've moved on," she said. "We're fine, so I think that's all that matters. Obviously, we're co-workers. We're Fed Cup team-mates. But other than that, everything else is private."

Azarenka dropped her first set of the tournament against Cornet but recovered to book her place in the last 16. A finalist last year and one of the favourites to win the title this season, Azarenka's next opponent is former world No 1 Ana Ivanovic, who also came from behind to win her Louis Armstrong Stadium clash with American Christina McHale 4-6, 7-5, 6-4.

Azarenka said: "In the first set, Alize played really well and I made too many mistakes. I wasn't patient enough. I had a lot of chances and I didn't convert them.

"The difference in the second and third sets was I played a bit more aggressively and when I got my chances I did convert them."

Another American, Alison Riske, 23 and ranked 95th in the world, reached the fourth round by beating seventh seed Petra Kvitova of the Czech Republic 6-3, 6-0.

Former Wimbledon champion Kvitova revealed afterwards that she has been struggling with a virus and will have more blood tests before returning home.

The 23-year-old said: "Unfortunately I was lying in bed yesterday and I had a fever, so I didn't come to the site."

Steve Brenner