It took awhile for both fighters to sign on the dotted line but the biggest fight that can be made without Manny Pacquiao was finally consummated on Wednesday when Floyd Mayweather Jr. signed to fight welterweight titleholder Shane Mosley on May 1 in Las Vegas.

Mosley signed the contract for the megamatch on Friday.

Mosley, who is ranked No. 3 in THE RING's pound-for-pound ratings, pursued a bout with both Mayweather and Pacquiao all last year to no avail. Pacquiao and Mayweather, Nos. 1 and 2 in THE RING's pound-for-pound ratings, appeared to be headed for what many thought would be the richest showdown in boxing history on March 13.

However, Mayweather's demand for Olympic-style random drug testing and Pacquiao's refusal to comply scuttled the super fight. Pacquiao subsequently signed to face welterweight contender Joshua Clottey on the March 13 date.

That opened the door for Mosley to fight Mayweather if the 38-year-old veteran won his bout with Andre Berto, which was scheduled for Jan. 30. However, Berto, a welterweight beltholder of Haitian descent, pulled out of the fight following the earthquake that hit the Caribbean island on Jan. 12 and killed hundreds of thousands of Haitians, including relatives of the undefeated young fighter.

The cancellation of Mosley-Berto opened the door for Mosley-Mayweather to be made immediately, and after about two weeks of negotiations — spearheaded by Richard Schaefer of Golden Boy Promotions, which represents both Mosley and Mayweather — the second best fight that can be made in 2010 was completed.

“This one is definitely for the fans as I wasn't going to waste anyone's time with a meaningless tune-up bout and asked to fight Shane immediately,” Mayweather (40-0, 25 KOs) stated in a press release sent out by Golden Boy Promotions on Wednesday. “I have said ever since I came back to the sport that I only wanted to fight the best. I think Shane is one of the best, but come May 1, he still won't be great enough to beat me.”

Mosley, who hasn't fought since demolishing Antonio Margarito in nine rounds last January, says he's eager to finally get back in the ring, especially against Mayweather.

“I have always wanted to fight Floyd and now it is finally coming true,” Mosley (46-5, 39 KOs) was quoted as saying in Wednesday's press release. “I am already in great shape and ready to show everyone on May 1 that I am stronger, faster and better than he is. I will have no problem beating him.”

In addition to the fight being one of the most competitive and talked-about contests in each of the fighters' careers, Mayweather and Mosley have agreed to the Olympic-style drug testing that Pacquiao refused.

“Floyd has been trying to make this fight for the last 10 years, so he is extremely excited about the opportunity to face Shane,” Leonard Ellerbe, CEO of Mayweather Promotions, stated in the press release. “He is also happy to set the precedent for random blood testing in order to ensure fair and safe contests for all fighters.”

The fight and a three-bout undercard will be produced and distributed by HBO Pay-Per-View, and the event is expected to be a blockbuster.

“Mayweather-Mosley is a showdown of superstars that fans have been talking about for years”, said Mark Taffet of HBO Pay-Per-View. “It has all the elements of a pay-per-view mega-fight.”