Spence knows Crawford well. Over a year ago, they fought in what was billed as a 50/50 contest. Crawford dominated that night, stopping Spence in the ninth round after scoring three knockdowns.
But Spence's experience with Mayweather goes back further. He sparred with the man known as 'TBE' (The Best Ever) during Mayweather's run at welterweight. People who watched described it as a real fight, not just sparring.
In a recent interview with Fight Hype, Spence shared his thoughts on the two champions:
"It's a big difference. Floyd is just different."
Spence rates Mayweather as potentially the best fighter of all time. If not the best, he puts him at "two or three, not by far."
What makes Mayweather stand out? Spence points out that Floyd was a lot older when they sparred, but still showed incredible skills:
"He was real tricky. He'd squeeze your nose in the clinch so you couldn't breathe. Veteran, all-time type stuff. Mentally, by far I feel like he's the best."
Spence is expected to return to the ring at the end of the year. He might face Sebastian Fundora, the current WBC super-welterweight champion.