Unbeaten junior welterweight Karim Mayfield took another step toward contender status by outpointing tenacious gate-keeper Mauricio Herrera in a 10-round HBO-televised bout from Verona, N.Y., on Saturday.

Mayfield (17-0-1, 10 knockouts), an unorthodox 31-year-old boxer-puncher from San Francisco, won by scores of 98-92, 97-93 and 96-94.

Most observers saw a close fight. Mayfield, who let his powerful hands go in spots, landed the harder punches and was generally more dynamic than Herrera (18-3, 7 KOs) but the hardnosed veteran from Lake Elsinore, Calif., was the busier and more consistent puncher as he constantly stalked forward.

The early rounds were marred by holding and grappling on the inside, most of which was initiated by Mayfield, but the bout heated up midway and ended with entertaining exchanges in the late rounds. Herrera scored with his jab, left hook and body shots while the stick-and-moving Mayfield landed big right hands.