Shakur Stevenson delivered the most complete performance of his career on Saturday night, outmaneuvering, outthinking and ultimately outclassing Teófimo López over 12 rounds to claim the WBO and lineal junior welterweight titles and become a four-division champion.

Stevenson cruised to a unanimous decision at Madison Square Garden by identical scores of 119-109, 119-109 and 119-109, numbers that reflected a fight largely contested on his terms from the opening bell. (The Guardian had it 118-110.)

In a contest between arguably the two best American fighters active today, framed all week as a clash between volatility and control, it was Stevenson’s composure and fistic acumen that defined the night. The unbeaten southpaw from Newark, New Jersey, dictated the tempo early, repeatedly forcing López into reset mode with sharp lead-hand work and disciplined foot positioning that prevented the champion from establishing rhythm or distance.

A rollicking crowd of 21,324 spectators – a record for boxing at the present-day Garden – arrived primed for chaos after a combustible fight week that included heated press conferences and a weigh-in melee. Instead, Stevenson turned the main event into something colder and more clinical, methodically dismantling López’s offense while fighting in the pocket and off the front foot for nearly the entire duration.

Stevenson (25-0, 11 KOs) established the geometry of the fight from the opening bell. He met López at center ring, touching him with his jab within seconds and following with clean left hands upstairs. López, born in Brooklyn’s Sunset Park neighborhood to Honduran parents, landed occasionally, drawing chants of “TEE-OH! TEE-OH!” from the lower bowl. But Stevenson’s advantages in hand speed, footwork and timing were immediately apparent.

Teófimo López, right, absorbs a blow from Shakur Stevenson on Saturday night. Photograph: Ishika Samant/Getty Images

The pattern only sharpened in the second. Stevenson landed the cleanest punch of the fight to that point – a flush shot that drew audible gasps – while continuing to push forward, undermining the narrative that he would box cautiously on the back foot. When Stevenson briefly went down, the referee ruled it a slip, and he resumed control behind a sharp jab and straight lefts that repeatedly split López’s guard.

By the third and fourth rounds, the contest had already tilted decisively. Stevenson’s educated jab – ramrod straight and delivered with blinding speed – neutralized López’s attempts to close distance. The champion struggled to find the target, often lunging at empty air as Stevenson exited exchanges at sharp angles. By the end of the fourth, the question inside the arena had shifted from who was winning to whether Stevenson might eventually force a stoppage. “Tonight I went out there and used my jab over and over and made it a weapon – and he couldn’t stop it,” Stevenson said.

López (22-2, 13 KOs) showed flashes of competitiveness in the fifth, attempting to increase output and vary his attack, but Stevenson’s jab continued to dictate terms. The sixth brought the first visible damage when Stevenson opened a cut over López’s left eye while continuing to walk his man down. López was investing heavily to the body, digging shots to Stevenson’s midsection, but the work produced little visible slowing of the challenger’s pace or sharpness.

By the seventh, frustration began to mount. López’s best hope seemed to lie in catching Stevenson in transition or baiting him into a mistake, but the challenger’s ring intelligence left few openings that weren’t accounted for. “I studied them. I studied them all,” Stevenson said. “Everything I saw on tape was there tonight. There is benefits from watching tape.”

Teófimo López lost all but one round on all three judges’ scorecards. Photograph: Cris Esqueda/Cris Esqueda Matchroom Boxing

López found his best stretch in the eighth and ninth rounds when Stevenson eased off the gas, perhaps conserving his energy for the championship rounds. López built on it in the ninth, letting his hands go and connecting with heavy body shots in one of his stronger rounds of the fight. But even then, the broader picture remained unchanged.

Any sense of momentum quickly faded. Stevenson reasserted total control in the 10th, delivering a masterclass in distance management and pacing. López, by contrast, looked increasingly desperate to create exchanges. By the championship rounds, the physical toll on López was visible. Blood trickled from the cut over his left eye entering the 11th, while a corner that had descended into chaos did nothing to slow it between rounds. López continued pressing forward but repeatedly ran into counters, Stevenson adding extra snap to his shots in the closing seconds.

The 12th unfolded as a formality. Stevenson boxed comfortably to the final bell, raising his gloves as the outcome felt inevitable long before the scorecards were read. Compubox’s punch statistics lent numerical context to the one-way traffic: Stevenson landed more than twice as many blows (165) as did López (72).

The result marked another milestone for Stevenson, who added a championship at 140lb after already claiming world titles at 126lb, 130lb and 135lb. Afterward, he said the performance reflected years of refinement rather than reinvention.

“This was the art of boxing: hit and don’t get hit,” Stevenson said. “I felt good. I picked him apart and I did what I was supposed to do.”