It’s funny how the unexpected moments in life often tend to be the ones which prove the most significant.

Case in point, who would have known that the instant Vernon Forrest snapped Shane Mosley’s head back with a wicked right hand, midway through the second round of their first meeting in January 2002, that he had just changed the course of Mosley’s life?

That right hand, along with the barrage that followed (and some might argue the headbutt that preceded it all) sent Mosley to the canvas in a heap for the first time in his career. Moments later, when he went down a second time, desperately trying to grasp at Forrest’s legs in an attempt to keep himself on his feet, Mosley unknowingly represented his equally desperate attempt to cling to his identity as a fighter.

Perhaps the single greatest fear of any man is to be exposed as a fraud, even if it is only a matter of outside perception. Call it pride or call it ego, but when the way in which someone defines himself is called into question, serious soul searching tends to follow.

Few likely considered Shane Mosley to be a fraud after his losses to Vernon Forrest, but no longer did anyone believe him to be an invincible force of nature either. Mosley’s career, reputation, and, most importantly, identity had been built upon a nearly unending series of conquests. All this had come to a screeching halt, and suddenly it was gut check time for Mosley. In the eyes of many, the two losses to Vernon Forrest spoke louder than the thirty-eight victories that came before them.

And just like that, at the age of thirty, Shane Mosley found himself in the midst of a mid-life crisis, but of a different sort than the one most men go through. The problem was, Mosley’s mid-life crisis could not be eased with a new motorcycle, hair plugs, or by dating a twenty-year old. Mosley would find his inner turmoil far more difficult to solve.

For a prizefighter, insecurities usually get magnified in the ring. It is an environment where facades crumble quickly, revealing the truth that lies beneath. This proved quite true for Mosley. Despite his high-wattage smile and self-assured words, watching him in the ring proved that something had soured in Sugar Shane.

In his return to the ring following the losses to Forrest, Mosley faced former 154-pound champion Raul Marquez, who was supposed to be a safe opponent and confidence builder for Mosley. As do many people who are facing a crisis of identity, Mosley instituted drastic changes in what appeared to be an attempt to reinvent himself. Against Marquez, the lightning quick, former lightweight champion was replaced by the new Shane Mosley, muscle-bound and sporting a bench press that would humble most gym rats. However, his heavily armored exterior did little to fix his dented psyche, and it showed as he struggled through a sluggish performance which ended, fortunately for Mosley, in a three-round no contest.

In his next bout, a rematch against rival Oscar De La Hoya, Mosley continued his desperate attempt to rebuild himself, which would ultimately lead to his notorious association with BALCO. Regardless of whether Mosley understood the gravity of his actions when he was using the substances in question, his use of performance enhancers was further evidence of his urgent need to rebuild his mental edge. The fact that Mosley got the controversial decision against De La Hoya did not seem to matter. The plainly visible truth was that Mosley was still not the same. The changes in him were subtle, but visible. Mosley’s once fluid confidence had been replaced by a split-second hesitation, a barely perceptible reluctance to engage that spoke volumes of the second guessing that was likely taking place in his mind.

Mosley’s funk continued with two consecutive losses to Winky Wright. Pedestrian performances against the less-than-stellar likes of David Estrada and Jose Luis Cruz further underscored the inevitable conclusion that Mosley’s days at the pinnacle of the sport were fast approaching their twilight. Even a decent performance against the faded Fernando Vargas in their first meeting failed to convince many that Mosley had many more fights left in him.

Then, suddenly, everything changed.

Just as one punch had started Mosley’s rather steep downhill slide, one punch marked the beginning of his ascent back to the mountain top.

The instant that his left hook concussively slammed into Fernando Vargas’ chin in the sixth round of their rematch, something reignited in Mosley. For the first time in nearly half a decade, Mosley acted on his fighter’s instincts without reluctance or trepidation. In that moment, he was in control, of his opponent and of his own fate. The follow-up assault which finished Vargas was brief and brutal, but it was far more than just a textbook example of how to finish a foe. It was one man emphatically reclaiming what was once his, his sense of identity as a man and as a prizefighter, and refusing to languish in the abyss of self-doubt any longer.

Subsequent fights have yielded both victories and defeat for Mosley, but the one constant has been his renewed sense of self-actualization. Shane Mosley has been to the brink and back again, and going through something like that makes a man feel stronger, even unbreakable.

Regardless of how Saturday night’s showdown with Floyd Mayweather turns out, Shane Mosley has already beaten the most difficult opponent in his boxing career: his own doubt and insecurity. The fact that he even has this opportunity to stand in the spotlight, even if it is for just one last time, is a testament to his will and perseverance. When a man has already stared down his own paralyzing insecurities, facing an opponent, even one as formidable as Mayweather, is a comparatively easy task. That is a comforting thought that Mosley will carry into the ring with him on the biggest night of his life.