Nonito Donaire caught in contract tussle

The ongoing battle between rival promotional companies Golden Boy and Top Rank was ratcheted up on Wednesday when Oscar De La Hoya's company announced that it signed unified bantamweight titlist Nonito Donaire to an "exclusive, multiyear agreement" and away from Bob Arum's Top Rank.

"Nonito Donaire is one of the top boxers in the world today and we're going to make sure he gets the chance to defend his world titles and stays as active as possible," De La Hoya said in a statement. "The bantamweight division is becoming one of the most competitive and exciting divisions in boxing and we look forward to promoting Nonito in great fights in the coming years."

Donaire has been with Top Rank since 2008 and scored the biggest win of his career on a Top Rank card Feb. 19 in Las Vegas, knocking out Fernando Montiel in the second round to win a pair of 118-pound belts on HBO.

That victory propelled the 28-year-old Filipino, also a former flyweight titleholder, into the top five on most pound-for-pound lists. Top Rank and HBO were so excited about Donaire's victory that they were already working on his next fight, a proposed May 28 bout against titleholder Anselmo Moreno or junior bantamweight titlist Hugo Cazares.

Top Rank has battled Golden Boy on several fronts over the years, most notably over the contract of another Filipino fighter, pound-for-pound king Manny Pacquiao -- which Top Rank won.

The signing of Donaire (26-1, 18 KOs) figures to produce yet another lawsuit between the companies.

"Top Rank has a valid contract and we will enforce our rights," Arum told ESPN.com.

Donaire, however, said he was happy to be with Golden Boy, although he did not address the status of his contract with Top Rank.

"I'm honored to be joining so many great fighters and champions on the Golden Boy Promotions team," Donaire said in a statement. "I'm going to fight my heart out every time I'm in the ring and will give fans the fights they want to see."

Golden Boy CEO Richard Schaefer also would not address the potential legal issues surrounding the signing.

"We are very excited he's with Golden Boy and I am looking forward to many great events with Nonito," Schaefer said. "I'm not going to get involved in any legal questions."

Schaefer said Golden Boy's intention was to arrange a fight for Donaire in May.

"I will meet with HBO and see that we can get him to fight in May," he said. "I don't know how the network will react to [the potential legal trouble]. I can't speculate on that."

Dan Rafael covers boxing for ESPN.com. Follow him on Twitter.