LAS VEGAS – Zhang Zhilei’s power was entirely too much for Scott Alexander to take Saturday night.

The huge Chinese heavyweight knocked out Alexander with a devastating straight left hand that knocked Alexander flat on his back in the first round. Referee Robert Hoyle quickly called an end to the action as Alexander clearly wasn’t fit to continue on the Canelo Alvarez-Dmitry Bivol undercard at T-Mobile Arena.

The official time of the stoppage was 1:54 of the first round. Alexander was still disoriented when he was helped to his feet, but he left the ring without assistance.

Zhilei, a southpaw who won a silver medal at the 2008 Summer Olympics in Beijing, upped his record to 24-0-1 and recorded his 19th knockout. Los Angeles’ Alexander (16-5-2, 8 KOs) lost by knockout for the first time in nearly 13 years as a pro.

The 6-foot-6, 276-pound Zhilei was supposed to face Croatian contender Filip Hrgovic (14-0, 12 KOs) in an IBF elimination match Saturday night. Hrgovic withdrew on short notice because his father died early in April and it prevented him from training properly.

Alexander officially replaced Hrgovic on Tuesday.

The Zhilei-Hrgovic fight will be rescheduled because it’ll determine the IBF’s mandatory challenger for the winner of the Oleksandr Usyk-Anthony Joshua rematch. has been informed that Zhilei-Hrgovic could be part of the Usyk-Joshua rematch.

Before Zhilei abruptly ended their fight Saturday, he trapped Alexander in his corner about a minute into their fight and tried to unload on his shorter, significantly lighter opponent. Hoyle warned Zhilei for holding Alexander down and hitting him during that sequence.

Prior to his loss to Zhilei, the 6-foot-3, 222½-pound Alexander hadn’t fought in the year since he lost to Puerto Rico’s Carlos Negron (25-3, 20 KOs) last May 1 at Dignity Health Sports Park in Carson, California.

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