At long last, pound-for-pound greats Floyd Mayweather Jr. and Manny Pacquiao will finally fight.

Yes, the fight that looms as one of the most anticipated in boxing history is finally on.

For more than five years sports fans have clamored for a summit meeting between the two best fighters in the world and after various failed negotiations — and a protracted and difficult effort to make the fight in recent months — they will get it on May 2 to unify their welterweight world titles at the MGM Grand in Las Vegas.

The showdown is a lock to be the richest in boxing history and will, barring a draw, settle the issue that has been debated for years: Who is the No. 1 fighter in boxing and who is the king of their era?

Mayweather made the announcement on Friday afternoon on a social media platform called Shots, of which he is an investor.

Many involved expected the announcement to come on Thursday but Mayweather was upset because Top Rank, Pacquiao’s promoter, was leaking word of the impending announcement and he wanted it to be a surprise.

According those familiar with the agreement, the contract Mayweather signed for the fight gave him the right to be the one to announce the fight, even though he was obligated to notify Top Rank of when he would do it. On Friday afternoon, Top Rank was notified and Mayweather made the announcement about an hour later.

Although he announced it on Friday the deal had been done for a couple of days with both sides having signed the paperwork. Contracts were also signed by broadcasters HBO and Showtime, who will team for a historic joint pay-per-view.