Roberto Duran knocked down Iran Barkley in the 11th round and won his fourth world championship title Friday night with a split decision that meant at least "uno mas" for the ancient warrior.

Duran, 37, showed flashes of the brilliance that carried him to the lightweight, welterweight and junior middleweight titles before he quit the ring in 1985, and in a war of arrogance versus hatred, the sheer determination of Duran won out.The man tagged as a quitter when he threw up his hands and walked away in the eighth round against Sugar Ray Leonard in 1980 forever and always erased the "no mas" memory with his courageous victory over Barkley.

Puffing and trying to catch his breath in the middle rounds, Duran summoned his last reserves in order to wrest the World Boxing Council middleweight title from Barkley. Duran won the 10th round with a left to the body, two lefts to the head and a right at the end of the round, and he stood head to head, toe to toe with Barkley to start the 11th.

The two traded punches evenly until, toward the end of the round, Duran landed two staggering rights to Barkley's swollen left eye.

Duran followed with a right, then a left, then a right, then a left, and finally another right as Barkley crumpled to the canvas.

Barkley, 28 and at 6-foot-1, 61/2 inches taller than Duran, regained his feet before the eight-count and made it to the bell. But that was it for the ungainly, sometimes awkward fighter.