AP Rafael Nadal

Mardy Fish will play Rafael Nadal in the quarterfinals of the U.S. Open Wednesday. On the surface, it's the story of the world's No. 1 against an American player whose having his greatest run at his hometown slam.

But dig a little deeper and you'll find a more intriguing business story.

As has been publicized, Nadal was supposed to wear a more conservative polo shirt during his play and looser, shorter pants.

Although Nadal's public relations person told The Wall Street Journal before the tournament that this was the Spaniard's choice, I knew from the start it couldn't have been. It was Nike's

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[NKE  Loading...      ()   ] choice. Why? Because just like Puma couldn't sell Serena catsuits, Nike can't sell cutoffs and tight capris to the average tennis player. Not only does the average tennis player not have the guns to showcase, but try wearing the cutoffs at a country club. And those pants? I've never seen one average Joe wearing those.

We know the story by now. Nadal said he couldn't get used to the attire in time and has worn his muscle T's and capris throughout the Open. Bottom line is it's a great look for Nadal and adds to his personality, but his clothing choice is admittedly bad for Nike's business.

Now let's focus on Fish, who is sponsored by K-Swiss

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[KSWS  Loading...      ()   ]. While Nike has still heavily advertised its affiliation with Nadal, Fish has been under the radar for K-Swiss -- which has chosen to upstage Fish with ads by using retired tennis player Anna Kournikova (who wore adidas when she was playing), Tommy Haas (who is now ranked No. 57 to Fish's No. 25) and Alona Bondarenko (who is No. 31 in the world and only got three games off Venus Williams in Flushing Meadows).

Unlike Nike, K-Swiss is a tennis brand and they can't really afford a situation like Nadal's: having a top star wear something that doesn't translate to the common folk. So since Fish switched from adidas

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[ADDYY  Loading...      ()   ] to K-Swiss late late year, he's been dressing in some of the most conservative outfits you've ever seen. On Sunday, for his big win over Gael Monfils, Fish wore what looked like a mostly plain white shirt with the K-Swiss logo on the upper left chest with a K-Swiss headband. He wore the black and gray versions for his night win against James Blake, but it's pretty much the same. Plain, blah, nothing special.

To the viewer, it might seem like K-Swiss -- which in July cut its outlook for 2008 off a 33 percent drop in revenue in the U.S. and flat international sales -- is missing out on an opportunity by not dressing up their unexpected star in a dynamic outfit like Nadal's. The truth is that given the game's participatory demographic, Fish's outfit is more likely to benefit from the exposure.

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