By Keith Idec

Joseph Diaz Jr. emphatically took his last step Thursday night toward the featherweight contender’s shot at Gary Russell Jr.

The undefeated Diaz floored former super bantamweight champion Victor Terrazas three times on his way to a third-round knockout victory in what was considered a tune-up fight for Diaz in Indio, California. ESPN2 televised Diaz’s win from Fantasy Springs Resort & Casino.

Diaz dropped Terrazas twice in the first round and once in third. Their scheduled 10-round fight for Diaz’s NABF and NABO featherweight titles was stopped at the end of the third round because Terrazas couldn’t get up from a vicious body shot Diaz landed.

The 25-year-old Diaz (26-0, 14 KOs), of Downey, California, is the mandatory challenger for Russell’s WBC featherweight title. The former American Olympians are expected to square off either in May or June.

By then, Russell, of Capitol Heights, Maryland, won’t have fought in more than a year.

The 35-year-old Terrazas (38-5-2, 21 KOs), a former WBC 122-pound champion, has lost three of his past five fights by knockout.

Before Diaz dismantled him Thursday night, Eduardo Hernandez (25-0-3, 21 KOs) knocked him out in the second round of their October 2016 bout in Mexico City. Two bouts before that defeat, Leo Santa Cruz (34-1-1, 19 KOs) knocked out Terrazas in the third round of their August 2013 fight in Carson, California.

Diaz nearly knocked out Terrazas in the first round.

He landed a straight left to Terrazas’ body that dropped him just 1:48 into their bout. Diaz also hit Terrazas with a right hook when Terrazas was down, which drew a warning from referee Edward Hernandez Sr.

Diaz dropped Terrazas again, this time with a left hook to his head, with 39 seconds remaining in the first round. Terrazas got up again and survived until the end of the round.

Diaz continued to attack Terrazas’ body in the second and third rounds. With 11 seconds to go in the third round, Diaz’s left hook to the body sent Terrazas to the canvas for the third time in the bout.

Terrazas remained on one knee until Hernandez counted to 10 and waved an end to the one-sided fight.

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