Photo by Jeff Gross/Getty Images

CARSON, Calif. — Viktor Postol knocked out Lucas Matthysse in the 10th round to win the vacant WBC junior welterweight title Saturday at the StubHub Center.

Postol did well in the fight, using his long jab keep a frustrated Matthysse at bay and win rounds, but the ending came as a surprise.

The Ukrainian knocked Matthysse to all fours with a straight right and the Argentine remained down for the count. The official time was 2:58.

A full report will follow.