SAN FRANCISCO -- Top Rank promoter Bob Arum told SI.com on Sunday that he has made his final offer to Floyd Mayweather and that Mayweather has until Monday morning to accept the deal. The offer remains essentially the same -- Pacquiao will submit to unlimited urine tests while agreeing to blood tests in January and as many as two more no later than 30 days before the fight.

The new wrinkle to the offer is that Arum is proposing a hearing be held on Jan. 19 in front of the Nevada Athletic Commission to determine whether additional blood tests are necessary.

"This is unprecedented," said Arum. "Our expert says blood tests are ridiculous. But we will let the commission decide. They are the governing body."

If Mayweather refuses, Arum says he will make a deal for Pacquiao to face former junior welterweight champion Paulie Malignaggi on March 13 in Las Vegas.

"That deal will take about an hour [to make]," said Arum.

The Nevada commission does not require fighters to submit to blood tests before a fight. Commission rules require fighters to take urine tests before and after each fight, tests that detect 40 different types of steroids, masking agents and diuretics.

Regardless of the outcome of the negotiations, Arum says Pacquiao plans to move forward with his defamation lawsuit against Mayweather. Golden Boy Promotions CEO Richard Schaefer, who is negotiating for Mayweather, could not immediately be reached for comment.

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