Is Federer your ultimate savior?

No one can dispute Rafael Nadal's unbridled on-court ferocity and intensity. Goh Chai Hin/AFP/Getty Images

In all the ways that matter most, the case for Roger Federer as the greatest tennis player ever is quite powerful -- a record 15 major singles titles, a career sweep of all four and this year he'll likely finish ranked No. 1 for the fifth time in the past six years. All this by the age of 28.

But greatness assumes many forms. Here is a question tennis aficionados like to pose: Who would you have play for your life? If the fate of the planet hung in the balance, if Satan held the keys to the kingdom, if all the chips were on the table, which tennis player would you want stepping in the arena?

Federer? Certainly not the man who melted -- virtually vanishing off the court -- in the fifth set of the Australian Open and U.S. Open finals earlier this year.

What's wanted in this ultimate match is a warrior of the highest caliber, a competitor who will be counted on to summon up every last physical, mental and emotional resource. This designate must drag the opponent through a battle so rough and tumble that no one will ever forget what took place. Even if the terms are changed -- an extra set, shifts in wind, sun and temperature -- this warrior will continue to bear down. Even if the planet is lost, the effort will have been tooth-and-nail. We lost, but we gave everything.

Here are the top five players, as tenacious as they come, I'd want playing for my life:

5. Monica Seles

As a child she was once playing a match when the umpire announced it was over. Said Seles, "Who won?" Here was someone utterly immersed in the moment. Seles' feet moved like pistons as she threw herself time and time again into her bazooka-like groundstrokes. Her intensity was off the charts. Best of all, her courage was relentless. Never did Seles back off; instead she was thoroughly committed to going for her shots. Per Billie Jean King, the ball doesn't know what the score is. It's just sitting there to be hit.

4. Rafael Nadal

If the fates decree the match of matches must be played on clay, surely Nadal must be the representative. The monkey wrench in the Federer Empire, Nadal's engagement, desire and hunger for competition is exemplary. Like Connors, he concedes nothing. Nadal's eyes, his movements, tenacity and imagination are everything you'd want in a competitor.

3. Billie Jean King

So much is made of King's off-court significance that it's easy to forget what made her such a great player. But remember, she was the delegate for an entire gender when she took on Bobby Riggs and handily beat him in straight sets. King likes to say, "I play the ball." But it takes a keen student and a superb athlete to recognize what the ball is saying and constantly make the right decisions about what to do with it. Against Riggs, for example, King adroitly altered her game plan with all the dexterity of a quarterback. But that was but one of hundreds of matches where King was able to bear down, probe and thrust, and conduct business with a long-term view at once gritty and aggressive.

2. Jimmy Connors

Across 20 years, Connors lived for the big occasion, throwing himself into his matches like a caged lion. Though Connors liked to say he never changed his game for any opponent, the truth is Connors was committed to giving his heart and soul to every point. But don't think he was tactically rigid. Like a shark sensing blood, Connors could smell a weakness -- and then drill away at it like a dentist whittling away a cavity. If it was impossible to watch Connors casually, it was even more implicating to take him on and sense everything from his churning feet to his over-the-top scowl. And make no mistake, he was as gladiatorial as they come, inspiring opponents to dig exceptionally deep. Consider: In each of the seven Grand Slam finals Connors lost, the victor played one of the best and most defining matches of his career. Surely Lucifer must play this well, too, if he's to take over Earth.

1. Pancho Gonzales

The serve is the most important shot in tennis. On a par with Pete Sampras' serve, the Gonzales delivery was smooth, powerful, accurate and reliable. But that was only the linchpin of a forceful competitive sensibility that won singles titles in four separate decades. In 1949, at the age of 21, Gonzales won his second U.S. singles title, fighting back from two sets to love down to beat another formidable competitor, reigning Wimbledon champion Ted Schroeder. In 1971, at 43, Gonzales won the Pacific Southwest Open -- then one of the 10 biggest events in the world -- taking out 19-year-old Jimmy Connors. Although Gonzales' first-rate serve was one key to his longevity, his strongest asset was the internal firepower, as big an appetite for competition as the game has ever seen.

Joel Drucker is based in Oakland, Calif., and writes for Tennis Magazine and Tennis Channel.