Unfortunately for Naomi Osaka, her first grand slam victory will forever be remembered for Serena Williams' incredible outburst on match umpire Carlos Ramos rather than for her fairytale win at the US Open final at the start of September. 

Osaka won the first set 6-2 as she took the game to the former world number one and 23-time grand slam champion and was firmly on course to win Japan its first ever grand slam. 

High drama then followed in the second set, Serena Williams received a code violation for coaching, a penalty point for racquet abuse and then a game penalty for calling the umpire a "liar" and a "thief" in an emotionally charged final. 

After the game, Williams accused Ramos of sexism. 

Talk was huge for days after the game with pundits and ex-players weighing in with their thoughts on who was right and who was wrong, and now one of the all-time greats, Roger Federer has had his say. 

Speaking to KVUE, Federer said: “It’s interesting but I think it’s important to look at it,” as per The Express. 

"Every umpire has their own style, it’s just how it is in any sport.

"In tennis you might have an umpire that gives more coaching violations and another guy goes more to time violation.

“You might get one guy who knows that this guy misbehaves quite often so I’ll give him a warning quicker or I’ll be more lenient with a guy because he’s a nice guy and just can’t control himself. I think it really depends on the situation."

On the allegations of gender bias, Federer said: “I hope it’s not the case, but I think what happened, obviously there was mistakes along the way and there should be more discretion sometimes.

“At the same time, they have to do their job, that’s what we want them to do.

“It’s been tricky but a really interesting case to study.”

Very interesting words from the evergreen Swiss. 

The American has kept pretty quiet with the days that followed the final as she has allowed others to talk and discuss what happened that night.

Serena Williams' next slam will come at the start of January in the Australian Open, where both herself and Carlos Ramos will be hoping events from the US open will be long forgotten.