The most anticipated bout between Floyd Mayweather Jr. and Manny Pacquiao is still possible if the Filipino boxer wins his fight against Brandon Rios.

Pacquiao is set to face Rios in Macau on Nov 23. This forthcoming match against the American boxer Rios is a do-or-die match for Pacquiao.

"This is Manny's most important fight," said Top Rank head promoter Bob Arum. "It is a must-win," Arum added.

Bob Arum appeared as a guest on a radio program in Australia on Monday where he made known that there is a big possibility for a Mayweather Jr.-Pacquiao fight. "If Pacquiao looks good, a Mayweather bout can definitely happen," Arum said.

Many boxing fanatics were left perplexed and discouraged because the on-again, off-again super fight between Mayweather and Pacquiao never gets settled.

"The only major problem is that Manny fights for HBO and Mayweather fights for Showtime," said Arum. "But they had a similar situation many years ago where Mike Tyson fought for Showtime and Lennox Lewis for HBO," he said. "If Manny shows that he is back, we can get it done," said Arum.

Arum believes that a fight between the undefeated boxer and Pacquiao is going to be great in the boxing industry.

Without a doubt, the dream fight is expected to earn huge amounts of revenue. However, don't you think Floyd and Manny would have done it already if it is only about money? This fight should have happened many years ago.

Mayweather stated on several occasions that Pacquiao is too good to be true, and that he is certainly not interested in fighting the Fighter of the Decade. More so, now that Pacquiao has lost twice consecutively, it just gives Mayweather more reasons not to entertain the idea.

Of course, a lot of people would still want to see the fight take place, but it is really difficult to imagine at the moment. Floyd is definitely on the rise, he had defeated Robert Guerrero and Canelo Alvarez impressively. Manny, on the other hand, is on a steady decline, having had lost to Timothy Bradley and Juan Manual Marquez in 2012.