Conor McGregor lost to Floyd Mayweather when he couldn’t handle one of the most fundamental differences of MMA and boxing

Isaac Brekken/AP

The Conor McGregor-Floyd Mayweather boxing match was stopped in the 10th round when it was clear that McGregor was on his way down, giving Mayweather the win by TKO.

After a surprisingly strong start, McGregor appeared exhausted in the later rounds of the fight.

By the 10th round, Mayweather was landing big punches to McGregor’s body and face as McGregor flailed against the ropes, not even throwing punches back.

Though there was some debate about whether the referee should have let Mayweather knock McGregor down — McGregor himself said he wished the ref would have let Mayweather knock him out — it was clear that McGregor was on his way down.

In the end, the fight essentially came down to fitness and one of the most basic differences between boxing and MMA — time difference.

McGregor had acknowledged this before the fight, noting that in UFC, he fought five five-minute rounds for a total of 25 minutes. In boxing, there are 12 three-minute rounds for a total of 36 minutes. Still, McGregor said he was training for 12 rounds and was not concerned. He said on “Conan” a week before the fight:

“We’ve made slight adjustments in my cardio preparation. It’s actually been very enjoyable to go from five, five-minute rounds, which is what we’re used to, which is 25 minutes, to 12, three-minute rounds of boxing, which is 36 minutes. Slight adjustments, but we are more than ready. I done 12 rounds last night, I’ve done multiple 12-round fights in the gym in the lead-up to this. We are more than ready.

“Floyd is praying for me to fatigue in there, but I will not fatigue. I will continue to press forward, and I will break him. At 40 years of age, he will not sustain my pace.”

However, it was clear by as early as the seventh round that McGregor was wearing down. His form had slipped and he was tying up with Mayweather more often. At one point in the ninth round, after the two fighters were separated, McGregor fell back into the ropes, unprompted.

After the fight, McGregor said Mayweather was not the hardest puncher, but was “composed.”

“He’s not that fast, he’s not that powerful, but boy, is he composed,” McGregor said. He added, “I was just a little fatigued. He was a lot more composed, especially in the later rounds.” McGregor also said he gets “wobbly” when he’s tired.

Without the experience and years of training, it was clear McGregor began to lose the form that was so impressive early in the fight. While he wobbled and generally looked drained later in the fight, Mayweather kept coming, looking not the slightest bit tired.

Here was the final seconds of the bout, in which McGregor was clearly out of gas.