Floyd Mayweather Says He Would Coach Ronda Rousey

Ronda Rousey could have a golden opportunity to improve her stand-up fighting game -- because Floyd Mayweather says he's willing to work with her ... if she'll give him a chance.

We got Floyd leaving Pristine Jewelers in NYC (he dropped roughly $200k on gifts for family and friends) -- when he told us he has nothing against Ronda and would love to help her out.

"I'll work with her if she's willing to work with me," Floyd said.

Ronda has blasted Floyd in the past over his domestic violence conviction. Floyd fired back by saying he makes way more money than she does.

But now, Mayweather says it's water under the bridge for him ... and it's her call.