UFC 158: Which Fighter Has the Most to Gain at Saturday's Event?

UFC 158 provides an opportunity of the highest order for one fighter on the UFC's stacked roster. 

This fighter is a welterweight. 

He is in the evening's main event. 

He is not the champion. 

Fighters fight to win championships—that is the ultimate goal of each and every combatant that steps into the UFC Octagon. 

For Nick Diaz, UFC 158 affords that much-desired chance at gold, and his career would be defined by a victory over Georges St-Pierre. 

Every title fight is huge, but when you have the chance to enter hostile territory, take down a champion—the UFC's poster boy—and halt one of the sport's most impressive winning streaks?

That is monumental. It is nearly impossible for a more perfect opportunity to present itself to a fighter, and Nick Diaz has the most to gain at UFC 158 because of this. 

Making the situation even more unique for Diaz, his inclusion in the championship bout is questionable at its core.

After failing his post-fight drug test at UFC 143, Diaz faced a yearlong suspension and a chorus of ridicule from fans who felt Diaz's "rebel" persona was officially out of hand. 

Thankfully for Diaz, Dana White and the UFC brass were not among those who felt such actions could not be tolerated, and the Stockton Bad Boy was awarded an immediate title shot upon his return to action. 

Whether or not this is deserved, Diaz naturally accepted the offer, and now he finds himself on the sport's greatest stage against arguably its greatest ambassador. 

Diaz is not supposed to win this fight. He is supposed to get wrestled to death and leave Montreal (and possibly the UFC) the night's biggest loser. 

He can change all that with one punch, one submission or one perfect 25-minute performance. 

Should he win this fight, Diaz will legitimize his status as an elite 170-pound fighter and take some heat off his past actions and statements. 

I mean, Nick Diaz says some crazy stuff.

He comes off as one part insecure, one part uneducated, one part incredibly bad-ass and one part genius to create what may be the world's most interesting man. 

If Diaz manages to defeat GSP at UFC 158, he will also become one part UFC champion, and that distinction is the most important of all. 

Win and all the glory is his.

Lose and an eager ensemble of naysayers awaits. 

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