Nonito Donaire-Jeffrey Mathebula set

Junior featherweight titlist Nonito Donaire, one of the top fighters in the world pound-for-pound, told manager Cameron Dunkin and promoter Top Rank that for his next fight he wanted an opponent who would motivate him.

That is what it seems he has gotten after a deal was agreed to Tuesday to match Donaire in a 122-pound title unification match with Jeffrey Mathebula of South Africa.

They will meet in the headline fight of a "Boxing After Dark" card on HBO at the Home Depot Center in Carson, Calif., on July 7, Top Rank vice president Carl Moretti told ESPN.com.

"Any time you can unify a title it's a good thing," Moretti said. "And any time you can unify the title in a meaningful division, which junior featherweight is, it's an even better thing. It's a legit fight. Mathebula is a little awkward and he's taller than Donaire. Matheubula is always in shape and has no reservations about coming to the United States for the fight."

Donaire (28-1, 18 KOs), the 29-year-old known as "The Filipino Flash," vacated his bantamweight belts to move up to junior featherweight in February and scored a ninth-round knockdown en route to outpointing former titleholder Wilfredo Vazquez Jr., to win a vacant title.

According to Dunkin, Top Rank offered Donaire fights with former junior bantamweight champion Cristian Mijares and featherweight prospect Robert Marroquin. But Donaire wanted a better grade of opponent -- and so did HBO -- leading them to Mathebula.

"It's a fight that Nonito asked for," Dunkin said. "Top Rank was offering us other fighters, Mijares and Marroquin to name two, but he wanted a unification fight. Nonito thought this guy (Mathebula) was a great fighter and would push him to the limit. Nonito said, 'I want something that will fire me up and this guy presents me with a challenge.' "

For one of the rare times in his career, the 5-foot-7 Donaire will be the shorter fighter. Mathebula is approximately 5-10.

"Nonito is usually the taller guy. He won't be for this fight, so I asked him if he wanted that problem," Dunkin said. "He said he did. He said, 'I want somebody that will really motivate me.' I said, 'OK.' I think this will motivate him but it's a dangerous fight, a scary fight. But it's what he wanted. He specifically asked for it."

Mathebula (26-3-2, 14 KOs), 32, claimed a title in March when he won a split decision against countryman Takalani Ndlovu in their rematch. Ndlovu won a split decision against Mathebula in their first fight, a title elimination match in September 2010.

Mathebula's only previous world title experience came in 2009 when he went to Celestino Caballero's home country of Panama to challenge him for his two titles and lost a disputed split decision.

Branco Milenkovic, who promotes Mathebula, said they were happy to be getting a fight with Donaire and the exposure in the United States that will go with it.

"I have worked with Top Rank before and again these negotiations were fair and we reached the deal," Milenkovic said. "Now I am excited that Jeffrey is getting an opportunity to fight a great fighter like Nonito Donaire. I know there were some other names being mentioned. I am not downplaying Mijares, but Jeffrey has more ability.

"If I believed Jeffrey had no chance to win this fight, I wouldn't make the fight. He can win the fight and he is excited to make his first trip to America to fight a big fight and be on HBO. Without a doubt, Nonito is the favorite. He's a great fighter, but I believe Jeffrey will come to win. My fighters always come to put on a good performance."

The HBO undercard has not been set yet but former lightweight titlist Brandon Rios, who is also managed by Dunkin, likely will open the telecast in a junior welterweight bout. Moretti said Rios' appearance was not locked in but Dunkin said he thought it would be Rios.

Dunkin said the most likely opponent for Rios is Mauricio Herrera (18-2, 7 KOs), 31, who is coming off a competitive 10-round decision loss to Mike Alvarado in an all-action slugfest that is a fight of the year candidate.

Rios (30-0-1, 22 KOs) lost his lightweight title on the scales in December when he failed to make weight for a fight with John Murray, whom he knocked out in the 11th round. On April 14, Rios, 26, was due to face Richard Abril for the vacant belt but again did not make weight and was ineligible to win the title.

The fight went on and Rios was awarded a highly controversial split decision in a fight most observers felt Abril had won easily. Herrera's fight with Alvarado was on the undercard.