Melvin Guillard burst onto the UFC scene at 22 years old, a gifted yet enigmatic talent that talked a bigger game than he actually brought with him at the time. Six years later, while his skills have improved greatly, most would say he’s still a gifted yet enigmatic talent.

In between, he rattled off a stretch of eight wins in nine fights, and just when we thought he was getting over the hump, he was rocked and finished in just 47 seconds by the competent yet usually light-hitting Joe Lauzon. The setback cost Guillard greatly, sending him off-course from a projected lightweight title opportunity.

Now 28 years old -- he turns 29 in two months -- the “Young Assassin” isn’t so young anymore. Where in the past, critics could at least see potential past his age, he’s reaching the point where he has to deliver against an established veteran.

That seems to be his Achilles heel. In scanning his fight history, you notice he has nearly always lost to fighters who stand up to his aggressive style, from Lauzon to Nate Diaz to Joe Stevenson and Josh Neer. The book on Guillard (29-9-2, 1 no contest) is that he wins the fights he’s supposed to win, but struggles in the limelight.

His Friday test against Jim Miller in the main event of UFC on FX 1 is the perfect setup to find out if the latest iteration of Guillard brings with it any evolution.

“I am ready for this fight with Miller,” Guillard said this week from Nashville, the site of the event. “He’s a top guy, maybe the No. 3 or No. 4 in the division, and if I perform like I can do, I think it will be hard for people to say that I didn’t deserve a UFC title shot.”

One of Guillard’s biggest issues has been his ground game, as all five of his UFC losses dating back to his debut have come by way of tapout.

Miller, a rugged grinder who recently saw his own seven-fight win streak snapped, presents the kind of skill set that has given Guillard fits in the past. He’s aggressive, he closes the distance, and he’s a finisher on the ground. Eleven of Miller’s 20 career wins have come via submission.

He’s also situated higher in the rankings than Guillard. All that has added up to a fight where Guillard is the underdog that must prove himself not only to the critics, but to himself.

“What happened last time [against Joe Lauzon] was a mistake,” he said. “I rushed in so hard and fast I was stunned with a jab and from there I lost the fight. It was kind of dumb, but I am young enough to learn as long as I realize the mistake. I made the mistake, it didn’t just happen. I know that, but I also know I’m still one of the best fighters in the division.”

In reality, Guillard isn’t wrong. By most objective measures he is still young. And he is one of the best 15 or so lightweights in the world. But the MMA world has been waiting a long time to see him reach his full potential. The sport is complex enough that we must offer some understanding when it comes to early struggles. But there is a limit to that grace period. You can only lose so many times before we realize the ceiling has been reached.

That is the situation Guillard is walking into on Friday. A two-fight losing streak isn’t a career-ender, but given everything that’s come before it, it would likely mean the end of his championship dreams. He knows the score. All he has to do to avoid the gatekeeper role is to do what’s been so difficult for him in these kinds of situations: win.

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Julie Jacobson / AP

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