Who wants to be the GOAT?

Story Highlights

'Goat' once had a negative sports connotation, but not the modern term 'GOAT'

Federer was widely considered the GOAT in tennis, but there's a case for Nadal

The GOAT is definitely playing at Wimbledon, we just don't know which one it is

Roger Federer (left) was once considered the GOAT of tennis, but Rafael Nadal (right) is making a strong case on his own behalf.

Cynthia Lum/Icon SMI

2011 Wimbledon

Day 13

GALLERY: Best photos from Sunday
WERTHEIM: 50 things from Wimbledon
JENKINS: Djokovic realizes his dream
WERTHEIM: Djokovic is the new king
Djokovic defeats Nadal for men's title
Nadal vows return to No.1 ranking
Kvitova jumps to No. 7 with victory
Australia's Barty takes girls' crown
Benesova-Melzer win mixed doubles

Day 12

SI Photos

All-Time No. 1s In Men's Tennis	Celebrities at Wimbledon
William and Kate Visit Wimbledon	Bethanie Mattek-Sands' Fashion Odyssey
Classic moments at Wimbledon	Wimbledon's trendsetters

Previous Coverage

Always, the worst thing you could call an athlete was: Goat. He's the chump who cost his team by dropping a fly ball, making a turnover, fumbling. Bill Gallo, the beloved New York Daily News cartoonist, would draw a portrait of the goat of every World Series game, depicting the poor stiff with horns for ears. In fact, I suspect the designation of the goat as the figure of ridicule derives from the medieval sign of the horn for a cuckolded husband.

Would it surprise you, then, to hear that now the best thing you can say about an athlete is that he is the GOAT in his sport? But this new GOAT comes without horns. Rather, it's an ancronym, and probably traces back to Muhammad Ali: "I am the greatest." Hence to Ali's Greatest of All Time, Inc. Get it: G ... O ... A ... T.

This is, of course, a subject that sports fans devour: who's the best ever? Most recently, for example, it was pretty well settled that Michael Phelps had become the GOAT in swimming. But don't jump on the GOAT bandwagon too fast. Tiger Woods was the GOAT gonna-be in golf, but Jack Nicklaus still holds the crown. And remember when Lebron James ... oh, never mind ...

Still, nowhere is there a more spirited GOAT discussion than in tennis. Not so long ago it was pretty much the consensus that Roger Federer had passed Big Bill Tilden and Rod Laver and Pete Sampras. He set the record for most Grand Slams, he was classically brilliant, the universal champion.

Only ... an embarrassing little hitch developed. Another player, Rafael Nadal, kept beating Federer. How can you be the Greatest of All Time if you're not even the greatest in your time?

Federer's GOAT defenders point out that the reason Nadal has a better head-to-head record is because Nadal is fabulous on clay, but Federer is terrific on all surfaces, so he gets to the clay-court finals, where Nadal beats him. But especially when Federer was at his peak, Nadal would lose in earlier rounds on other surfaces, so Federer didn't get to sweeten his head-to-head score against his rival.

Besides, Federer has set records for superior consistency that are unreal: making 18 of 19 Grand Slam finals in a row and making 23 straight Grand Slam semis, and 28 quarterfinals and still counting.

That's sort of combining the best of the streaks of Joe DiMaggio and Cal Ripken.

But, wait: Nadal is five years younger and if his body holds up, he could easily pass Federer's record for most Grand Slam victories.

So, it's undoubtedly a GOAT situation we've never had before ... in any sport. We know the greatest tennis player of all time is playing right now ... this week, in fact, at Wimbledon. We just don't know who he is.