By Joseph Santoliquito

PHILADELPHIA, PA (CBS) — The date is set. The venue is set. Manny Pacquaio is set. The purse split is set. The drug testing is set. Even the types of gloves each fighter will wear are set. All the boxes have been checked for the mother of all fights between Pacquiao and Floyd Mayweather are a go for May 2, at the MGM Grand in Las Vegas—except one. The missing piece is Mayweather’s signature on the contract for a fight that will shatter the 2.4-million pay-per-view buys garnered by Mayweather and Oscar De La Hoya in 2007.

It’s a fight that Mayweather now has to make.

Mayweather (47-0, 26 KOs) will turn 38 on February 24. He’s been this generation’s best fighter and the face of boxing for the last 10 years. But if he doesn’t make this fight now, the blame will lie solely with Mayweather, and it will stain the rest of his career.

Top Rank, Pacquiao’s pomoter, confirmed everything that Mayweather has wanted, including the 60-40 split favoring Mayweather.

Bob Arum, Top Rank’s chairman, said negotiations have been ongoing the last few months through CBS CEO Leslie Moonves, who signed a six-fight with Mayweather to appear on Showtime. The drug-testing protocol, which originally negated the possibility of a Mayweather-Pacquiao fight in 2009, has been agreed on by Pacquiao, using the U.S. Anti-Doping Agency that has tested all fighters on Mayweather shows.

What’s more is neither Pacquiao (57-5-2, 38 KOs) or Mayweather are getting any younger. The time to move would be now. Pacquiao is 36, but won’t turn 37 until December 17. But there is plenty of wear on the Filipino dynamos tires.Since talk of the Mayweather-Pacquiao fight in 2009, “Pac-Man” has suffered two defeats, one a dubious upset to Tim Bradley, the other a sixth-round TKO to Juan Manual Marquez in December 2012, with Pacquiao ahead on all three scorecards.

It’s reached a point where Mayweather has basically run out of excuses for not fighting Pacquiao. The fight is six years beyond its peak sell-by date to boxing cognoscenti. But the boxing community and the passionate media that covers the sport will be pointing a crooked index finger at Mayweather if it doesn’t happen this time.