THE bout between Floyd Mayweather and Manny Pacquiao at the MGM Grand Garden Arena in Las Vegas on Saturday night is the richest and most eagerly-anticipated in history and for a while it seemed like Amir Khan didn't want to add to the hype.

At first, the Bolton fighter - who shares the same weight class - declined to challenge the winner, but after being chastised for his reticence by his former coach, and Pacquiao's long-time trainer, Freddie Roach, it appears the gloves are off.

"Now, look, I'm making this official," said the 28-year-old, who is currently resident in San Francisco as he prepares for next month's fight with Chris Algieri in New York. "Yes, I would fight the winner of this fight. Obviously, I have so much respect for these guys, Manny Pacquiao and Mayweather, that I didn't really want to say anything because I didn't want people thinking I'm a bit cheeky for calling the winner of such a big fight before the fight even happened. But it's not because I'm afraid."

Khan will be in Vegas to watch the contest which has been six years in the making. It may not be the fight it would have been back then, when both men were at their peak, but Khan will savour the occasion purely as a boxing spectacle - albeit as an observer with a vested interest.

He has been chasing a bout with Mayweather, unbeaten in all 47 of his previous fights, for two years, but time is running out. The 38-year-old from Grand Rapids, Michigan, is planning to return to the ring just once more before retiring, but it is in September, a month which Khan usually regards as unsuitable due to limited training time after observing Ramadan. A crack at Pacquiao later in the year seems a more achievable option, but much depends on the outcome on Saturday night.

"I know Floyd has a quick turnaround after the May fight ... and God forbid, anything can happen, he might get injured or something," said the 2004 Olympic silver medallist, who moved up to welterweight in 2013. "So we just have to stay strong and keep performing well, and if it happens we're going to be ready."

Khan believes the contest could rank alongside epics such as the "Rumble in the Jungle" between George Foreman and Muhammad Ali in Zaire, in 1974. As for the outcome, he says: "I favour Floyd Mayweather, because he's not been beaten and I think he's a better boxer. The first four or five rounds will be competitive. But after that I think Floyd will take the lead and probably start winning the fight, creating that distance. Styles make fights, and Mayweather's style suits this fight because he's a taller guy, he has a longer reach, he's got quick hands.

"Maybe a couple of years ago this would have been an even bigger fight. Since Pacquiao's had a couple of losses it takes the stakes down a bit. But it is still a massive fight. When you've got two TV networks working together it shows how big it is."

Sky Sports Box Office will show Mayweather v Pacquiao exclusively live on May 2. Buy now at skysports.com/maypac or from April 25 via your Sky Box