The business at welterweight continues to churn forward. IBF champion Errol Spence Jr. is set to take on WBC champ Shawn Porter in a welterweight unification bout scheduled for Sept. 28 at The Forum in Los Angeles, California, Premier Boxing Champions announced on Saturday afternoon.

Spence is coming off a destructive decision win over Mikey Garcia in March where he nearly shutout the previously unbeaten champion who moved up two weight divisions to take on the challenge. Porter scored a split-decision win over Yordenis Ugas in March to defend the belt he earned in a decision over Danny Garcia in September 2018.

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"You try to box me, let's see what happens," Spence said during the first press conference. "I'll put you on your ass. I showed you boxing skill against Mikey Garcia. This one will be different."

Spence (25-0, 21 KOs) has long pursued his opportunity to be called the undisputed champion at 147 pounds, but still needs to bait WBO titleholder Terence Crawford into a matchup if that is to happen. The winner of this bout is likely to take on the winner of Saturday's main event between Manny Pacquiao and Keith Thurman.

"That's something I definitely want to do -- clean out the division. Terence Crawford is still out there. I want to reign supreme over everyone," Spence said.

The co-main event will feature super middleweights Anthony Dirrell and David Benavidez squaring off with Dirrell's WBC title on the line. The winner of that fight could meet up with the winner of Saturday's featured bout of Caleb Plant and Mike Lee later on in 2019.