Making a case for the top dogs

For a while there, men's tennis was essentially a one-man show each year.

Four times in the past six years, a single player won three of the four Grand Slam singles titles. Roger Federer (2006-07) did it twice, followed by Rafael Nadal (2010) and Novak Djokovic (2011).

It won't be happening this year. Not even close. The field has leveled dramatically, and maybe, just maybe, the big four is something more than a cartoon creation.

Nine years ago, four men won the four majors of 2003: In order, Andre Agassi, Juan Carlos Ferrero, Federer and Andy Roddick. In tennis terms, that was a generation ago -- and the last time tennis was so open to suggestion.

This year, we have seen Djokovic prevail over Nadal in a spectacular, nearly six-hour match in Australia. We watched Nadal beat Djokovic to win his record seventh title at Roland Garros and Federer score his record-tying seventh Wimbledon crown. Andy Murray lost that final at the All England Club but followed with a breakthrough gold-medal performance at the Olympics.

Although that popular victory doesn't count toward his major total -- Murray is still at zero -- it was significant. Coming into the U.S. Open, which begins Monday, Djokovic, Federer and Murray have one huge win apiece on their 2012 résumés. Nadal, of course, will be sitting this one out as he mulls a medical strategy to solve the tendinitis that has ravaged his knees.

Still, in this year of the value-added Olympic Games, the tournament in New York will go a long way toward determining the player of the year. That isn't always the case.

"It's a great scenario," said ESPN analyst Brad Gilbert, who coached Agassi. "Every one of those guys has something to play for."

It would be natural to think Murray, after going 0-for-4 in finals this year, including the Wimbledon loss, might have found the confidence to reverse that trend. ESPN analyst Darren Cahill, who coached Agassi and Lleyton Hewitt to the top of tennis, isn't quite ready -- as former football coach Bill Parcells liked to say -- to put Murray in the Hall of Fame.

"I still think it's very difficult to place him with those other great players," said Cahill, who had a hand in bringing Murray together with his new coach, Ivan Lendl. "Remember, they've still won 29 of the last 30 majors. Obviously, Andy deserves his place after winning the Olympics as a Grand Slam champion in the making.

"Winning the Olympics will be a huge confidence boost for him. But he still has to do it over two weeks, in a best-of-five-sets format."

Justin Gimelstob, a Tennis Channel analyst, begs to differ.

"The two guys I'd keep an eye on are the guys with momentum," he said. "That would be Murray and [Juan Martin] del Potro. Murray winning the gold and Delpo finishing strong for the bronze -- that bronze match is one of the toughest matches to play in tennis -- sets us up with a legitimate top five.

"I truly believe these four guys, along with Rafa, represent the golden age of tennis. You can make a compelling argument in New York for all of them."

Here is a closer look at the three leading favorites:

The Case for Federer

He's Roger Federer.

Even at the age of 31, Federer finds himself in a time capsule, coming off a victory at Wimbledon and an emphatic defeat of Djokovic in the Cincinnati final and holding the No. 1 ranking.

"Since last year's U.S. Open, he's been remarkable," Cahill said. "Roger, I think, is going to be in position to win Grand Slams the next couple of years. He's done an incredible job the last few years of keeping himself mentally and physically prepared."

In Cincinnati, Federer's serve was never broken as he won his fifth title there. When he won the first set from Djokovic 6-0, Federer, in some minds, became the leading candidate for a victory in New York.

Gimelstob saw it coming. In the 2011 Tennis Channel year in review, he predicted Federer would win a Grand Slam and go to No. 1.

"It's amazing," Gimelstob said. "The other guys are in their prime. That he wrestled [Wimbledon] away from them in their prime is one of the greatest accomplishments we've ever seen."

The Case Against

He's 31.

Federer played a 4-hour, 26-minute semifinal match against del Potro in London, prevailing 19-17 in the third set, and, clearly, he was physically depleted in the final against Murray. Will playing five matches in Cincinnati compromise his health and well-being in New York?

Although Federer should be a factor at Wimbledon for the next several years because the grass suits the diversity in his game, the U.S. Open is a more physically punishing tournament. The back-loaded schedule and the windy, sometimes steamy conditions could work against him.

The Case for Djokovic

Djokovic has won three Australian Open titles, but he's nearly as comfortable in New York, with three finals appearances in the past five years. He's 33-6 at the U.S. Open, where he is the defending champion, compared with 32-5 Down Under.

"He loves hard courts," Cahill said. "His best tennis, his best results have come in New York. He'll be looking to get his game back."

Djokovic was the only member of the big four to make an impression in Toronto, and despite losing to Federer in Cincinnati, he had a good look at winning the second set. He seems committed to salvaging his season -- after the best year of his life.

"It looks like he's maybe a little more disconnected and unstable, but 2011 was an impossible standard to maintain," Gimelstob said. "I think he's the favorite. The sum of all his parts, his offensive and defensive skills, served him well at the Olympics, which bodes well. He's not the one they're all hunting, like last year, but he's back in the hunt."

The Case Against

After winning three majors a year ago, Djokovic hasn't been the same in terms of intensity.

"It's been a huge 18 months for him," Cahill said. "But who knows how much it's taken out of him physically and mentally? I don't think he's lost much confidence. I'm just feeling like he's looking for that inspiration."

Said Gilbert, "He could turn around his year massively here. You can say if he wins the Open, he's won five majors in two years and he's probably the No. 1 player in the world."

That said, the impressive 2011 season seems to be weighing on Djokovic.

"I mean, he didn't lose until the French Open last year and his second loss was in Cincinnati," Gilbert said. "You can't relive something like that."

The Case for Murray

He's ready.

Murray, who lost the 2008 U.S. Open final to Federer, is coming off his greatest victory ever in London.

"That was huge," said Gilbert, who once coached the Scot, who is 25. "Obviously, it wasn't Wimbledon, but for him it was important. To say Andy is ready would be an understatement."

Gimelstob was part of NBC's broadcast team at the Olympics.

"What stuck with me was that Murray used the disappointment of losing Wimbledon," he said. "Instead of spiraling and digressing, I really sensed he used it as motivation and a building block. You could just tell physically and emotionally he was locked in.

"I wouldn't be surprised if there is a Lendl effect. Lendl lost his first four major finals and then broke through. Like they say, it's tough to win without confidence. It's tough to get confidence without winning. Andy Murray, instead of swimming upstream, now he's paddling down."

The Case Against

He has never won a major.

For Cahill, it simply comes down to previous performance.

"Listen, the Olympics was a great effort," he said. "I'm guessing he considers it the biggest moment of career, but just don't jump the gun. I don't want to paint him as a favorite at the U.S. Open. I think you have to give respect to the other three guys with Grand Slam wins under their belts."

Gilbert: "It's going to be who can maintain their health, mentally, physically. Who can navigate their way through the first week of the U.S. Open with the least amount of damage? Always, after Wimbledon, Murray usually does three weeks of training in Miami. With the Olympics, he wasn't able to do that. But it's the same for everyone."