We all saw it, that beautiful uppercut Conor McGregor landed under Floyd Mayweather's chin in the very first round of their much-hyped August 26 fight.It was just one of a number of punches the Irish UFC champion landed on the still undefeated Floyd Mayweather.However, there was another one you might have missed.In the run up to the fight, few commentators had confidence in the Irishman.Some said he would fail to land any punches on Mayweather at all, especially with Money's greatest asset being his ability to avoid shots from some of the stiffest fighters in his weight class.Though he is the first, and only, two-weight UFC champion, McGregor had zero professional boxing matches going into the bout and was making his debut against one of the best boxers of his generation, Floyd 'Money' Mayweather. McGregor lost the fight due to a referee stoppage in the 11th round, but still, he landed a whopping 111 punches on Mayweather, surpassing Manny Pacquiao's paltry 81, and giving a performance far greater than predicted by many.McGregor himself focused on that first round uppercut after the fight, as he said: "I tell you what, I hit him with an uppercut and it just missed. It just hit him here (the chest) and then hit him here (the jaw)."But if it was just that millisecond earlier, it would have just hit him there (the jaw) and that would have been all she wrote."He's not wrong, but in the wake of the fight, pundits have been picking over the footage and found a clean left in the fourth round.Coming at the end of a two-sided exchange, the Notorious ducks a right-hand and springs back with a beautiful left hand on Mayweather's jaw.Watch the unnoticed sweet shot McGregor landed in the video below.

Renowned for his power, McGregor's shot clearly rocks Mayweather.

Had the Irishman had just that much more energy by the fourth, that left-hand shot might have done it.