Tim Bradley Jr. to defend title

Welterweight titlist Timothy Bradley Jr. and Mexican star Juan Manuel Marquez, both known for their history with Manny Pacquiao, are going to fight each other for Bradley's 147-pound world title, Top Rank promoter Bob Arum told ESPN.com on Tuesday.

They are due to meet Sept. 14 -- Mexican Independence Day weekend, a date that usually is the target for a major fight involving a top Mexican boxer -- at the Thomas & Mack Center in Las Vegas in the main event of an HBO PPV card.

"The fight is agreed to. We have contracts out to both fighters," Arum said. "[Top Rank president] Todd [duBoef] worked hard with both sides and [Marquez co-promoter] Fernando [Beltran] worked hard with Marquez and we came to terms with both of them."

A victory would put Marquez as the only fighter in Mexico's storied boxing history to win world titles in five weight classes. He already has won titles at featherweight, junior lightweight, lightweight and junior welterweight.

"It would be a very significant thing for Marquez to win another title," Arum said.

"These guys wanted to fight each other, too. They really wanted to fight each other, even though either of them could have opted to fight Manny. But Bradley-Marquez is an interesting fight. People are going to see an action fight. Marquez is an action fighter, and Bradley showed he's not afraid of slugging with anyone like he did [last month] in the fight with [Ruslan Provodnikov]."

Marquez agreed to the deal to face Bradley last week, Arum said, after which Marquez talked openly about the fight, even though Bradley had not yet come to terms.

Bradley, however, reached a "deal in principle" Monday night, manager Cameron Dunkin told ESPN.com.

"We do have a contract but [Bradley and his wife, Monica] want to make some changes, but none of the changes are financial that I know of. It's been agreed to in principle," Dunkin said.

"It's a terrific fight and an action fight. I like my guy to win, of course, but I think it's gonna be a really, really fun fight that people will enjoy. You've got two of the best boxers in the world. These are guys that know how to fight and who are not afraid to bang and who are tremendously skilled."

While the fight is slated for Sept. 14, Arum said he would move the match to Oct. 5 or Oct. 12 if Floyd Mayweather Jr. winds up going on the same date, in order to avoid a conflict with Golden Boy Promotions for a second consecutive year.

Mayweather is scheduled to defend his welterweight crown against Robert Guerrero on May 4 on Showtime PPV but has said all along that he planned to return Sept. 14.

Last year, the companies clashed on Sept. 15, causing bad feelings all around. Top Rank promoted the Sergio Martinez-Julio Cesar Chavez Jr. middleweight championship fight at the Thomas & Mack Center on HBO PPV, while rival Golden Boy promoted Saul "Canelo" Alvarez's junior middleweight title defense against Josesito Lopez on the same night on Showtime down the street at the MGM Grand Garden Arena.

"If Mayweather is going to fight on Sept. 14, we'll move our date," Arum said. "But this prevents anybody from bait-and-switching us. We talked to the [pay-per-view] industry about it. Nobody is looking to make trouble. We're just looking to protect our position.

"Marquez and Bradley is a huge fight, especially with Hispanics, so we'd like to do it on Sept. 14. Nobody can say we're jumping Golden Boy's date. We have a date in reserve in case Mayweather fights on Sept. 14, which I don't believe he will wind up doing. If he doesn't, we will go on Sept. 14. If [Golden Boy chief executive Richard] Schaefer is going to bait and switch and try to put in some other fight on Sept. 14, he won't get away with it. But if Mayweather fights then, fine. We'll move."

For Marquez, the lure of the fight is the chance to win a world title in a fifth weight class.

"There were talks with two possible candidates for Sept. 14," Marquez told ESPN Deportes. "We talked about Mike Alvarado and Timothy Bradley. But I love important challenges, the most difficult ones, and to me it would be a great challenge to fight Timothy Bradley, who is also the world champion. And to me it would be a great challenge to fight him and also to try to win a fifth title in another division, which to me is something very pleasing and would bring me a lot of pride. Right now, that's the biggest challenge -- and I love the biggest possible challenges."

The 39-year-old Marquez (55-6-1, 40 KOs) is coming off his most significant victory, a sixth-round knockout against Pacquiao on Dec. 8 in Las Vegas in the fourth fight of their great rivalry.

There was discussion that Pacquiao and Marquez would meet again for a fifth time in their next fights, but both decided to go in other directions.

Pacquiao, instead, will return in October or November to fight in Macau, China or Singapore. Arum said he will face either interim junior welterweight titlist Mike Alvarado or Brandon Rios, who have split a pair of slugfests. Arum said whoever gets the fight with Pacquiao would move to an undetermined catch weight of more than 140 pounds but less than 147 pounds.

Marquez, with his clean knockout of Pacquiao, said he was looking for a new challenge rather than facing Pacquiao again, even though Pacquiao still leads their series 2-1-1.

"Look, what is being said about Pacquiao -- that a fifth fight wouldn't make sense -- well, it's just like that," Marquez told ESPN Deportes. "It still doesn't make sense. To me, it wouldn't be a challenge, and I need challenges. I would like to close my career in good standing and leave a legacy behind me. I want everyone to remember me for having faced the best fighters out there, and I believe Timothy Bradley is one of them. And why not look forward to finding that fifth title in a fifth weight class, which is something no one here in Mexico has achieved?

"So to me this is an important challenge, a difficult challenge, a tough challenge. But I always have the mindset that anything can be achieved."

Bradley (30-0, 12 KOs), 29, of Palm Springs, Calif., is a former unified junior welterweight champion who moved up to welterweight and claimed a world title in June 2012 with a massively controversial split decision against Pacquiao.

Bradley made his first title defense against Provodnikov on March 16, winning a unanimous decision in which Bradley was nearly knocked out in the first and second rounds and also survived a clean knockdown in the last 15 seconds of the fight.

Arum said he believes the fight can generate a strong buy rate on pay-per-view.

"I think we can do 500,000 or 600,000 buys," Arum said. "We think the lowest is 400,000, with a shot at 600,000. Marquez is now bigger in Mexico than Chavez Jr. after the way he beat Manny, and Tim is coming off that great fight with Provodnikov. People know a good fight."