Justin Fortune, the strength and conditioning coach for WBA "regular" welterweight champion Manny Pacquiao, is not convinced that Floyd Mayweather will take part in a potential rematch with the Filipino superstar.

Mayweather won a twelve round unanimous decision over Pacquiao in May 2015, in what became the most lucrative boxing event in history.

Mayweather and Pacquiao have crossed paths several times since their showdown, and there was talk of a rematch in 2019.

The rematch is much easier to make, with both boxers now aligned with powerful boxing adviser Al Haymon and his Premier Boxing Champions banner.

Pacquiao was in action back in January, and won a dominant twelve round decision over Adrien Broner.

Fortune believes the performance by Pacquiao, now 40-years-old, may have swayed away Mayweather's interest from doing a second fight.

Mayweather retired from the sport in September 2017, after stopping UFC superstar Conor McGregor in ten rounds.

After that fight, Mayweather stayed away from the boxing ring - until he decided to take an exhibition fight on New Year's Eve, when he traveled to Japan and blew away Tenshin Nasukawa in one round.

Fortune believes the rematch will have to happen in 2019 or it may never happen, because the two guys will be two old and the interest will not be strong.

“I think Floyd may not be interested in another fight against Manny,” said Fortune to The Philippine Star.

“Manny looked good against Broner and maybe, Floyd’s not too keen on risking his undefeated record. That zero in Floyd’s record is important to him. To me, I don’t think it’s that important. Floyd hasn’t fought a real contender in a while. If the rematch doesn’t happen this year, it may not ever happen. If you wait until next year, they’ll be a year older. Floyd will be 43. Fans might lose interest in a rematch if they’re kept waiting too long.”