Timothy Bradley to defend belt at Marlins Stadium Dec. 15

Palm Springs’ Timothy Bradley will make his first defense of the World Boxing Organization welterweight title he won against Manny Pacquiao Dec. 15 at Marlins Stadium in Miami, his promoter announced Friday.

Although an opponent hasn’t been officially signed yet, the fighter mostly likely to land the fight is former welterweight champion Andre Berto, according to a source close to the negotiations but unauthorized to speak publicly on the matter.

Bradley promoter Bob Arum said HBO, which will televise the Dec. 15 fight, was unable to help broker a deal with rival promoter Richard Schaefer to make Robert Guerrero (30-1-1, 18 KOs) Bradley’s opponent.

Guerrero and his camp lobbied hard to fight Bradley on Twitter and in other forums. Schaefer had previously said he wouldn’t stand in the way of allowing Arum’s Top Rank to promote a bout his fighter wanted.

“The problem is Schaefer,” Arum said. “He did have a problem with that.”

Schaefer did not immediately return a message left at his Los Angeles office.

Another person close to the negotiations, but not authorized to speak publicly, said at this point that both Bradley and Guerrero are asking for too much money to make the fight.

Bradley (29-0, 12 knockouts) won a controversial split-decision over Pacquiao June 9 in Las Vegas despite many at ringside believing Pacquiao had won at least nine of the 12 rounds.

South Florida’s Berto (28-1, 22 KOs) hasn’t fought since September 2011 after testing positive for a steroid before his scheduled June 23 bout against Victor Ortiz at Staples Center.

Berto was dumped from the card, and recently had his license reinstated by the California State Athletic Commission, citing the trace amounts of contamination in his drug test.

Arum would only say he’s “finalizing an opponent now, a top welterweight, and we should have it done next week” for the Bradley bout.

Arum said Marlins Stadium officials contacted him about the fight because “they know after we’ve done shows at Yankee Stadium and Cowboys Stadium, we know how to do these things.”

Marlins Stadium has a retractable roof and Arum said he is hopeful to draw 20,000 to 25,000 fans with low-priced tickets and a card that will include former two-time Olympic champion Guillermo Rigondeaux (11-0) of Cuba.

Rigondeaux is the World Boxing Assn. super-bantamweight champion. The card also will likely include former Russian Olympian Matt Korobov and Mike Lee, of Subway sandwich commercial fame, Arum said.

“This will be a huge attraction, we’ll make it a fiesta,” Arum said.

Update 2:02 p.m.:

Schaefer told The Times Friday that he represents Berto and is not at all convinced that Arum wants Bradley to fight either Guerrero or Berto. Instead, Schaefer thinks Arum would rather settle for former Manny Pacquiao sparring partner Ruslan Provodnikov (22-1, 15 KOs).

“I told HBO this would happen, that Arum never believed I’d play along and let Guerrero fight Bradley,” Schaefer said. “Once we did, Arum is saying Guerrero priced himself out. Typical Arum.

“He hasn’t talked to us about Berto. Who is he talking to? He wants an easy fight and HBO is empowering him. It has nothing to do with money...HBO is getting played.”

lance.pugmire@latimes.com

Twitter.com/latimespugmire

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