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 referee 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.

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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:
“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.



