Nadal vs. Djokovic: What to Watch for in Highly Anticipated 2013 US Open Final

Over the past three years, Novak Djokovic vs. Rafael Nadal has become the top rivalry in tennis.

The two competitors have met 36 times overall—more than any other two men in the Open era—including five times in Grand Slam finals. With a sixth major championship showdown ahead on Monday, only Nadal and Roger Federer have met more times on the sport's grandest stage. 

But while Nadal has had Federer's number in recent years, Djokovic-Nadal has been as even as it gets. 

The world No. 1 won seven straight matchups with the clay-court legend from 2011 to 2012 but has dropped five of his last six meetings coming into Monday's can't-miss clash.

So, who will own the next chapter in tennis' best rivalry?

Here we'll break down what to watch for in the 2013 U.S. Open Men's Championship. 

When: Monday, September 9 at 5 p.m. ET

Where: Arthur Ashe Stadium, Flushing Meadows, N.Y.

Watch: CBS

Live Stream: US Open Live

What to Watch For

The Opening Set 

The winner of the opening set has gone on to win the last six matchups between these two rivals.

As mentioned, Nadal has won five of the last six meetings. But it's important to note that he won the first set without a tiebreak on each of those five occasions.

It's also worth noting that Nadal has beaten Djokovic just twice after dropping the opening set. The last time Rafa bounced back to beat Djokovic after losing the first set was at the 2009 Madrid Masters in a best-of-three-sets semifinal. 

The only other time was at Wimbledon in 2007 when Djokovic retired in the third set. 

On the other side, Djokovic has gone on to beat Nadal three times after losing the opening set, most recently in the 2012 Australian Open final. He also battled back twice on hard courts in 2011 to beat Rafa after falling behind early.

Therefore, the opening set will be much more important for Nadal than it will be for Djokovic on Monday. Rafa hasn't shown an ability to overcome Djokovic when he falls behind early while the latter has fought back to win three times over Nadal in the past 30 months, including in a major final less than two years ago in Australia.

Marathon Match

Regardless of which player wins the opening set on Monday, fans can brace themselves for a long championship match.

Each of Nadal and Djokovic's previous five Grand Slam finals have gone at least four sets, with four of the five lasting at least three hours and 40 minutes. Their last hard-court Grand Slam final in Australia turned into a record-breaking match.

Djokovic would win in five sets, but not until after nearly six hours had passed, making it the longest Grand Slam singles final in the Open era.

Their two previous U.S. Open final collisions have run about four hours in length. Therefore, like The New York Post's Marc Berman suggests, you'd be wise to clear your schedule for Monday night:

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