LAS VEGAS – Charles Martin moved one step closer Saturday night toward earning another heavyweight title shot.

The former IBF champion knocked out fellow contender Gerald Washington in the sixth round on the Deontay Wilder-Tyson Fury undercard at MGM Grand Garden Arena. Martin knocked down Washington with a left hand with 1:12 to go in the sixth round.

Washington landed flat on his back. He got up quickly, but referee Tony Weeks determined Washington shouldn’t continue.

The time of the stoppage was 1:57 of the sixth round.

By winning this IBF championship elimination match, Martin (28-2-1, 25 KOs) became that sanctioning organization’s second-ranked challenger for a shot at champion Anthony Joshua. England’s Joshua won the IBF belt for the first time by knocking out a then-unbeaten Martin in the second round of an April 2016 title fight at O2 Arena in London. 

Joshua is expected to make a mandatory defense of his IBF title against Bulgaria’s Kubrat Pulev (28-1, 14 KOs), the IBF’s number one contender, in his next fight.

Washington (20-4-1, 13 KOs) suffered the TKO defeat of his seven-year pro career. Before Martin stopped him, Wilder, Jarrell Miller and Adam Kownacki defeated the former USC football player inside the distance.

Martin, a Las Vegas resident raised in St. Louis, hit Washington with a straight left hand to affected Washington several seconds before a second left sent him to the canvas in the sixth round.

Martin landed a straight left with 1:20 to go in the fifth round, which made Washington hold him.

A straight left by Martin made Washington stumble late in the fourth round. Washington swung wildly and missed with a right hand early in the fourth round.

Washington landed a right about a minute into the second round. Martin snuck in a straight left with approximately a minute to go in the second.

Washington connected with two hard, right hands with under 30 seconds to go in the first round. That made Martin fire back with a straight left that backed up Washington.

Martin attempted to follow up once Washington went to the ropes, but Martin couldn’t connect with another flush punch.

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