Among the many people who still doubt that Manny Pacquiao and Floyd Mayweather will duel in May is rapper 50 Cent who recently expressed his reservations on the rumored fight.

In a tweet, Sports Illustrated's Chris Mannix said that 50 Cent told him in an interview that he doubts Mayweather will agree to fight Pacquiao because "he's scared to death."

Fox Sports said that the undefeated American fighter and 50 Cents used to be buddies but their friendship fizzled out. It noted that the rift began a few years ago, when the rapper started criticizing Mayweather on Twitter for allegedly avoiding strong and talented opponents. The boxer hit back by commenting on the decline of the record sales of 50 Cent.

In 2012, MTV reported that Mayweather did not only mock the rapper for his music career but also referenced on the incident where the rapper got shot nine times in 2000. "I respect the shooter not the one who got shot," the boxer was quoted by the same report as saying.

Doubts on the fight of the two greatest boxers of their generation started surfacing when Showtime executives revealed that the fight talks are in progress.

"Floyd Mayweather has agreed to the fight, but there are deal points still to work out but progress is being made," Showtime spokesperson Chris DeBlasio was quoted by New York Daily News.

Despite the delay, Top Rank CEO and Pacquiao's promoter Bob Arum is convinced that the fight will push through. Hopefully, the camps will finally agree on the conditions of the match soon.

"We're making progress. It's going in the right direction. Everybody looks like they're digging down to make this happen. We're just trying to complete the paperwork. I say a couple of days because Floyd has dug in to fighting on May 2 and every day it takes to finalize the fight it takes away from the promotion of it," Arum told New York Daily News.

Many people are already awaiting for the final details of the fight since May is fast approaching and there are still no concrete plans coming from both camps.

Pacquiao's camp earlier espressed that they will give Mayweather an ultimatum or else they will move on and find other boxers willing to fight him.

On the other hand, Mayweather has reiterated in interviews that the fight will happen. In fact, after watching the match between the Miami Heat and Milwaukee Bucks recently, he even went to Pacquiao's hotel room to discuss the fight privately. What's causing the delay is still unclear at this point.