Horns career-best win came back in 2017 when he arrived out of nowhere to beat boxing-legend Manny Pacquiao for the WBO welterweight strap.
Despite the diehard Pacquiao fans that will tell you their man was robbed, Horn deserved the win. He snatched the opportunity with both hands, fighting relentlessly to steal the rounds from the far more experienced and talented champion.
Horn had two things going for him in that fight. Firstly, Pacquiao almost certainly underestimated him - when a man with Manny's resume takes on somebody as inexperienced as Horn was, it's pretty much impossible not to.
Secondly, and perhaps the real key to the upset, is that Horn was a total unknown. Had Pacquiao any idea what Horn would bring to the fight he'd likely have trained harder and trained more specifically for Horn's style.
Since being launched into the spotlight on the back of the Pacquiao win, Horn is 3 from 6, and with his opponents knowing exactly what he has to offer, it would appear that his brief foray into the upper echelons of the sport might be coming to an end.
Horn is a very good fighter - you don't win a world title from Manny Pacquiao if you aren't - but if he hopes to get back to boxing at that level he'll need to add something to his repertoire. The Bullish head-first style will only take him so far, and when it fails as it did against Tszyu, he'll have to have something else up his sleeve.
You could argue that it's too late in the game for Horn to improve his boxing, and it may well be, but that's not to say that his career is over. Horn is absolutely capable of being competitive within the mid to lower levels of the top 10 and he could put together a solid record at that level.
However, with his opponents now knowing exactly what to expect, and seemingly without any other dimensions to his game, Horn may find that the Manny Pacquiao's of the world are now far from his reach.
The post doesn't have any comments just yet. Why not be the first?