An all-time great rolls into the US Open final having one of the best seasons of his career. His big-serving opponent is far less experienced, though, and everyone predicts a three-set rout.

Brad Gilbert has read this script before. During the 1999 US Open men's final, Gilbert was coaching four-time Grand Slam champion Andre Agassi, who was the heavy favorite to beat first-time finalist Todd Martin.

But the match didn't go quite as predicted, Gilbert remembered, and he has a warning of caution to anyone forecasting a 90-minute Rafael Nadal route of Kevin Anderson on Sunday: “I don't think so,” Gilbert told

Anderson, like the 6-foot-6 Martin did against Agassi, has the potential to disrupt Nadal's game with his big serve and potent forehand. The 6-foot-8 South African leads the tournament with 114 aces, an average of 19 a match. He's also erased 24 of 33 break points, including all 14 during his first three rounds.

Nadal has struggled against big hitters on quick courts, Gilbert noted, especially in recent months. The Spaniard fell to 6-foot-4 Aussie Nick Kyrgios a few weeks ago in Cincinnati, and he was knocked out of Wimbledon in July by 6-4 Gilles Muller of Luxembourg.

“That's first and foremost. [Anderson] has to serve really well and take care of his serve,” Gilbert said.

How well Anderson fends off break points will be particularly important to watch as Sunday's final progresses. Nadal has been 2013-dominant – the year he won 10 titles, including his second US Open – this fortnight. He dismantled Juan Martin del Potro during their semifinal, dropping only five games in the final three sets.


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But the 31-year-old has been susceptible to slow starts in New York, and, Gilbert said, he seems to need a break of serve before playing free. Facing Japan's Taro Daniel in the second round, Nadal lost his first three break chances in the opener but cruised once he broke in the second set, winning three straight sets.

His third-round match against Leonardo Mayer of Argentina followed a similar pattern, with Nadal dropping his first 13 break points. Yet once he broke, he rolled.

“He never relaxes until he breaks at least once,” Gilbert said.

It could be hours until Nadal breaks Anderson. In the 1999 final, Agassi broke Martin in the first game but then didn't break for another two hours and after he'd fallen behind two sets to one.

The second key to an Anderson upset, Gilbert said, will be pouncing on Rafa's second serve. When the South African gets a look, Gilbert said, he needs to swing big.

“He has to be very aggressive on Rafa's second-serve return,” Gilbert said.

If Anderson can do those two things well, Gilbert said, 23,000 fans and millions more across the world might watch a five-set final unfold in Arthur Ashe Stadium, one reminiscent of the battle between Agassi and Martin 18 years ago. Agassi eventually prevailed in that all-American clash, 6-4, 6-7, 6-7, 6-3, 6-2, in three hours, 23 minutes.

"I think it will go either four or five sets," Gilbert said.

He does have a caveat, though. If Anderson lands only 60 percent of his first serves and hits only single-digit aces, the "experts" could be right.

“He's no picnic to play against," Gilbert said, "and obviously the one thing that can cause troubles or concerns is if he has a poor day serving."