SAHUARITA, Ariz. (AP) - Kassim Ouma, dethroned as IBF junior middleweight champion last summer, won a minor title Friday night with an eighth-round knockout of Francisco Mora.

Ouma sent his Argentine opponent sprawling with a straight left, tapping him on the chin with a right as he fell, at 2:34 of the eighth. Mora was up at eight, but referee Bobby Ferrara stopped the fight, which was for the vacant North American Boxing Organization title.

"I was working on him, tap, tap, tap," said Ouma (23-2-1). "I drop a combination on him, every now and then hit the body; the fight is over. He's going to quit or else they going to stop the fight or something."

In two undercard bouts, unbeaten junior lightweight Vicente Escobedo won his ninth straight fight by knockout when he stopped Jesus Salvador Perez of Colombia in the sixth round, and David Lopez of Mexico knocked out Shay Mobley in the eighth round of a scheduled 10-round middleweight bout.

Ouma, one of boxing's compelling stories after being kidnapped by the National Resistance Army in Uganda when he was seven years old and seeing combat in a civil war as a youngster, won the IBF crown in 2004 and held it until July 14, when Roman Karmazin outpointed him in Las Vegas.

But he made sure it wasn't left up to arbitration this time.

Ouma tagged Mora with a short right early in the second round and two compact rights to the jaw coming out of a clinch that never materialized. Near the end of the round, Ouma dropped Mora to the seat of his pants for the first of the bout's two knockdowns.

In the seventh, Mora opened strongly, knocking Ouma backward with a right, but negated that with a low blow later in the round.

Trainer Ronnie Shields said he cautioned Ouma about attacking too early because of Mora's history in heavier weight division. Both weighed 154 pounds for this fight, but Mora has fought at 160 and 168.

"(Ouma) is sitting down more on his punches," Shields said. "I think he could have knocked him out, but I realized he's fighting a bigger guy. "This guy is coming down."