Mike Golic and Ryan Clark are onboard with the prospect of a rematch between Floyd Mayweather and Manny Pacquiao. (1:47)

The moments before the opening bell of any big fight are typically filled with anticipation and tension, but there are few cooler customers than Manny Pacquiao.

Pacquiao, calm and cool as always, saw retired rival Floyd Mayweather sitting ringside with his daughter -- courtesy of tickets Pacquiao had arranged for them -- on Saturday night at the Thomas & Mack Center in Las Vegas. Mayweather outpointed Pacquiao in their long-anticipated May 2015 megafight, for which they both earned boxing-record nine-figure paydays.

Upon noticing Mayweather on Saturday, Pacquiao’s face lit up and he pumped his fist. Then the bell rang, and Pacquiao proceeded to take apart Jessie Vargas to win a dominant decision and reclaim the welterweight world title that Pacquiao lost to Mayweather.

"Not only for myself, but the fans of boxing (who) want the rematch, then why not. We can easily talk about that. It is not a problem. Because we now have direct contact to them, it would be easier to talk about when there will be a rematch." Manny Pacquiao on a possible rematch with Floyd Mayweather

Mayweather’s presence, of course, led to immediate speculation of a possible rematch for the richest fight in boxing history (to the tune of $600 million!).

In the context of Mayweather’s ringside perch, it made Pacquiao’s performance appear to be an audition for a rematch. If that’s the case, Pacquiao passed the test, dropping Vargas, cutting him and rolling to victory.

After the fight, Top Rank promoter Bob Arum cut short the postfight news conference because Pacquiao was delayed, and it was going to take him another 45 minutes or so to arrive. He had to get 16 stitches in his scalp thanks to a 12th-round head butt and also had to produce a urine sample for his Voluntary Anti-Doping Association drug test.

Former pound-for-pound king Floyd Mayweather sat ringside to watch Manny Pacquiao's domination of Jessie Vargas. Christian Petersen/Getty Images

Pacquiao was apologetic for missing the news conference, and he welcomed some reporters to his hotel suite at The Wynn resort on Sunday afternoon to discuss the fight and also field the inevitable questions about Mayweather.

While Mayweather’s mere presence at the fight -- he normally doesn't attend bouts -- made it clear his retirement could be coming to an end for the rematch, Pacquiao made it clear he is open to a sequel.

"Not only for myself, but the fans of boxing (who) want the rematch, then why not,” Pacquiao said. "We can easily talk about that. It is not a problem. Because we now have direct contact to them, it would be easier to talk about when there will be a rematch."

Personal contact between Pacquiao and Mayweather at a Miami Heat game and a meeting in Mayweather’s hotel room after the game helped finalize the 2015 fight.

Arum: Pacquiao rematch with Mayweather likely Manny Pacquiao will "definitely" fight again in the spring, and promoter Bob Arum says "I give it 75 percent" that it'll be a rematch against Floyd Mayweather. Read

Pacquiao said the Mayweather camp notified his team the day before the Vargas fight that Mayweather would attend.

"I met with his manager. I told him I would invite Floyd, and they said OK," Pacquiao said.

But while he is interested in the fight, Pacquiao said there have not been any specific talks. He was anxious to return to the Philippines and his job as a senator (which he resumed Tuesday). There will be time for their camps to talk if Mayweather wants the rematch and wants to exit retirement.

“There’s no talk of a rematch, but if there is, we can easily talk,” Pacquiao said. “It’s not a problem between us.”

If there is no Mayweather rematch, Pacquiao said he could go down to junior welterweight to challenge undefeated unified champion Terence Crawford; they share Arum as a promoter. Arum is also talking up a possible fight between Pacquiao and gifted two-time Olympic champion Vasyl Lomachenko, a junior lightweight world titleholder. Arum envisions that potential fight at lightweight.

Manny Pacquiao, right, lost a one-sided unanimous decision against Floyd Mayweather in 2015. Al Bello/Getty Images

“Imagine me back at 135 pounds,” former lightweight titleholder Pacquiao said with a laugh. “I can do it; 140 is my natural weight. I need to eat five times a day to make 147, and sometimes I throw up from eating too much.”

As for other name fighters at welterweight, Pacquiao was unmoved when titleholders Keith Thurman and Danny Garcia were mentioned..

“Oh, they’re champions? Good for them,” Pacquiao said.

Clearly, Pacquiao (59-6-2, 38 KOs) has his eye on Mayweather (49-0, 26 KOs), which is by far the biggest fight either of them could make in terms of money and attention, even if the first fight was a huge disappointment.

Pacquiao said he was hampered by a shoulder injury in the fight, after which he had rotator cuff surgery. The fight was hard to make and took so long to schedule -- five years! -- that Pacquiao said he did not want to call it off and risk it never happening.

"I have no regrets because I felt good one week before the fight,” Pacquiao said. “In that kind of fight, I hurt my shoulder.”

Pacquiao promised that if they fight again, it will be better than the 2015 fight, which was a commercial smash but a critical bust.

“If the rematch happens, I want to make sure the fans love it,” Pacquiao said. “I will give it all I could just to get back the trust of the fans.”