In a last-ditch effort to save the proposed March 13 megafight between Manny Pacquiao and Floyd Mayweather, representatives of both fighters will meet Tuesday in the office of retired federal judge Daniel Weinstein in Santa Monica, Calif., to try to revive talks between the sides through mediation.

Top Rank chairman Bob Arum, who will represent Pacquiao at the mediation along with Top Rank President Todd DuBoef, said Sunday night the only way that talks will resume is for Mayweather’s side to drop its demands for random blood-testing, and to apologize publicly to Pacquiao for previously implying that the Filipino superstar and seven-time world champion was taking illegal performance-enhancing drugs.

“Absolutely, from every single one of them,” Arum said of the apology. “Everybody.”

Mayweather’s side originally said it wanted Olympic-style, random blood-testing to be done by the U.S. Anti-Doping Agency, but has since softened on that demand. Pacquiao has said he is reluctant to have his blood tested within 30 days of the fight.

Neither fighter has ever tested positive for any banned performance-enhancing drugs.

Arum said he has “no feeling one way or the other” whether the mediation can be successful in saving the possible welterweight fight at the MGM Grand in Las Vegas. If the dispute can’t be resolved over the next few days, there’s still a chance the sides can come to an agreement later and the fight pushed back to May or later in the summer.

Arum also said he was under a gag order and couldn’t comment on whether Pacquiao’s lawsuit against Golden Boy Promotions — which represents Mayweather for this fight — for defamation of character would be part of a mediation settlement.

Pacquiao’s lawyer, Daniel Petrocelli, filed a lawsuit last week seeking $75,000 in compensatory and punitive damages. Petrocelli will be present at the mediation.

The Tuesday meeting at Weinstein’s office was first reported by AOL Fanhouse.