Kendo Castaneda caught Sonny Fredrickson with a left hook that abruptly ended their junior welterweight fight in the first round Friday night.

That flush punch knocked Fredrickson flat on his back with 1:04 to go in the opening round at ProBox Events Center in Plant City, Florida. A stunned Fredrickson struggled to get to his feet, which forced referee Chris Young to halt their scheduled eight-rounder 2:02 into it.

San Antonio’s Castaneda (18-5, 9 KOs) advanced to the semifinals of ProBox TV’s “Last Chance Tournament” in the 140-pound division. He’ll face the winner of the following fight Friday night – another eight-rounder between China’s Zhiming Wang (11-3, 3 KOs) and American Joseph Fernandez (12-1, 4 KOs).

Fredrickson (21-6, 14 KOs) has lost five consecutive fights. The Toledo, Ohio, native has been knocked out in back-to-back bouts as well.

Keith Idec is a senior writer/columnist for BoxingScene.com. He can be reached on Twitter @Idecboxing.