By Richard Pagliaro | Tuesday, July 18, 2017

Roger Federer and Rafael Nadal have never faced off in Flushing Meadows, but the upcoming US Open is a major crossroads in the iconic rivals’ chase for the world No. 1 ranking.

World No. 1 Andy Murray concedes his grip on the top spot is slipping and former No. 1 Novak Djokovic has slipped to No. 4 struggling with an elbow injury that could require surgery.

Watch: Federer On Keys To Longevity

Meanwhile, a revitalized Federer and resurgent Nadal have split the Grand Slam spoils this season charging within striking distance of seizing the top spot.

Fresh off winning his record eighth Wimbledon championship permitting just eight games in a royal rout of a skittish Marin Cilic, Federer suggests the race for year-end world No. 1 ranking may well ultimately come down to Roger vs. Rafa.

“I think it's going to be a three or four-way race,” Federer told the BBC. “Or maybe a two-way race with me and Rafa at some stage, when Andy is going to drop his world No 1 ranking. But if all of a sudden Andy starts winning again, we also have to win again. But at some stage if he starts dropping points, we'll just get there.

Tennis is a numbers game.

Ranking points to a Rafa vs. Roger race for the top over the next four months.

Currently, Nadal, who fell in an epic four hour, 48-minute thriller to Gilles Muller in the Wimbledon fourth round, trails Murray by just 285 points for No. 1.

The 10-time Roland Garros champion is defending just 370 points over the rest of the year, including 160 ranking points for his 2016 US Open fourth-round finish.

The third-ranked Federer pulled the plug after his 2016 Wimbledon semifinal exit in order to rehab his surgically-repaired knee.

That means the eight-time Wimbledon champion, who celebrates his 36th birthday on 8/8 with dinner scheduled at 8, has no points on the line the rest of the season. Federer (6,545 points) currently trails Murray (7,750) by 1,205 ranking points.

Barring injury, the 19-time Grand Slam champion is in the driver’s seat for the upcoming North American hard-court track, which typically plays fast to suit Federer’s all-court attack. The five-time US Open champion reached the Flushing Meadows in his last appearance there two years ago. Federer has surged into the US Open semifinals or better in 10 of his last 12 appearances.

Two years ago, Federer toppled then world No. 1 Djokovic, 7-6 (1), 6-3, to capture his record seventh Cincinnati title. While there is speculation Federer will skip the Rogers Cup, he is planning to play Cincinnati.

In contrast, Murray is facing a massive mountain of 5,460 ranking points for the rest of the season. That includes 3,500 points on the line later in the season when he defends Masters 1000 championships in Shanghai and Paris followed by defense of his ATP Finals championship in the season-finale in London.

Pained by a nagging hip injury that left him hobbled, Murray lost 12 of the last 14 games in his Wimbledon quarterfinal thrashing at the hands of 28th-ranked Sam Querrey, who knocked then world No. 1 and reigning Wimbledon champion Djokovic last year.

The deposed champion, who was also depleted by a bout with the shingles earlier in the year, departed his home major with the resignation of a man who knows his days at the top are numbered.

“I mean, it was going to happen at some stage. I don't think anyone has ever stayed at No. 1 their whole career,” Murray said at Wimbledon. “It always comes to an end. I haven't played well enough this year to deserve to stay there for much longer.”

The end of Murray’s reign could come during the upcoming North American Masters season or in New York.

“If it doesn't happen by the end of this tournament, it will happen, by the end of the US Open. That's fine. Obviously I would rather be ranked No. 1 than 2, 3 or 4. You know, I go away now and try and find a way to get back there. Hopefully I can do that.”

Federer has a different hope in the race to regain the top.

“I hope it's me and not Rafa,” Federer told the BBC, “because it would mean a lot to me to get back to world No 1. I have to speak to the team and decide how much am I going to just chase it in the near future so maybe I get to world No. 1 at least one more time in my career.

“Or is it actually maybe a goal to finish the year as world No. 1, which is an even bigger deal? But for me maybe that makes no difference being world No. 1 for a week or year-end No. 1 at this stage of my career. So I have to just have a bit of a meeting and discussion with my team about that in the coming weeks.”