O’Shaquie Foster fought brilliantly Saturday night in what he considered the most meaningful fight of his career.

Foster felt disrespected because he was treated like the "B" side of a fight in which he was supposed to be the defending champion. Stephen Fulton fueled him, too, by making dismissive comments and failing to make weight for their scheduled 130-pound championship match.

Even more motivated than usual to prove a point, Foster performed masterfully and dominated Fulton on the Isaac Cruz-Lamont Roach pay-per-view undercard at Frost Bank Center in San Antonio. His impressive, convincing victory was evident on the cards of judges Ester Lopez (118-110), Doug Robinson (119-109) and Chris Tellez (117-111).

Foster, 32, won the WBC interim lightweight title in his first fight in 13 months. Foster (24-3, 12 KOs), of Orange, Texas, was scheduled to defend his WBC super featherweight crown, but Fulton came in two pounds overweight Friday.

The WBC inexplicably sanctioned Foster-Fulton as a 135-pound title fight later Friday, despite the Mexico-based sanctioning organization had already approved Ricardo Nunez and Jadier Herrera to fight for its interim title January 10 in New York.

Philadelphia’s Fulton, 31, failed in his bid to become a champion in a third division. Fulton (23-2, 8 KOs) previously won world titles in the junior featherweight and featherweight divisions.

Before Saturday night, undisputed junior featherweight champ Naoya Inoue was the only opponent to defeat Fulton, whom the Japanese superstar stopped in the eighth round of their title unification fight in July 2023 in Tokyo.

Foster’s jab remained a weapon in the 10th, 11th and 12th rounds, when Foster fought mostly from a southpaw stance. Fulton seemed resigned to a lopsided loss as they headed toward the championship rounds.

Foster landed a left that knocked Fulton backward early in the ninth round. Fulton bled from his mouth in that round and had fallen way behind on the cards.

A straight left by Foster connected 40 seconds into the eighth. Fulton was aggressive at the start of that round, but Foster prevented him from getting into a rhythm.

Foster fought from a southpaw stance in the fourth. He flustered Fulton with his movement and elusiveness and remained in control.

A sharper Foster dictated the action with his jab in the third, with Fulton having difficulty getting punches off.

Foster was more active in the second round, though neither fighter landed any consequential punches in it.

Fulton lunged forward and landed a left hook with about 40 seconds on the clock in the first. Foster connected with a right hand soon thereafter in what was a tactical opening three minutes.