LAS VEGAS – Sebastian Fundora feels he has proven himself to be ready for the winner of the Jermell Charlo-Brian Castano rematch.

Fundora’s fantastic showing during his technical knockout of Erickson Lubin on Saturday night didn’t just make him the WBC’s interim super welterweight champion. It proved that the 6-foot-6 Fundora isn’t some limited novelty act who was destined to lose once he fought a top 154-pound opponent.

The 24-year-old Fundora dropped Lubin late in the second round with a well-executed right uppercut. He mostly took Lubin’s power well, too, apart from the sequence in which the Coachella, California, native absorbed an array of flush punches from Lubin and went down to one knee late in the seventh round.

Eventually, Fundora’s punches had done so much damage to Lubin’s face that Lubin’s trainer, Kevin Cunningham, stopped the action mere seconds after the ninth round ended. As BoxingScene.com reported Sunday, Lubin suffered a broken nose and a separated right shoulder that’ll require surgery during their “Showtime Championship Boxing” main event at Virgin Hotels Las Vegas.

Meanwhile, the undefeated Fundora suddenly had a signature victory 5½ years into his pro career. As the WBC’s mandatory challenger for whoever wins the second bout between Charlo and Castano, a confident Fundora (19-0-1, 13 KOs) hopes he gets that fight next.

“If we can win all the belts at once, why not? You know?,” Fundora told a small group of reporters after his impressive victory over Lubin. “I want the champion next. This is only a little step towards it. But the next one’s the real thing, hopefully. If not that, we’ll fight anybody at 154. We’re doing good.”

The 26-year-old Lubin (24-2, 17 KOs), a southpaw from Orlando, Florida, had done well since Charlo knocked him out with one punch in the first round of their WBC championship match in October 2017 at Barclays Center in Brooklyn. He took a six-fight winning streak into his showdown with Fundora, which emerged as a “Fight of the Year” candidate.

Now that Fundora has joined Charlo as the only opponents to have beaten Lubin, he will watch closely when Houston’s Charlo (34-1-1, 18 KOs) and Buenos Aires’ Castano (17-0-2, 12 KOs) fight again in another “Showtime Championship Boxing” main event May 14 at Dignity Health Sports Park in Carson, California. Unless their rematch ends in another draw or a no-contest, Charlo or Castano will become boxing’s first fully unified 154-pound champion of the four-belt era.

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