Undefeated Shakur Stevenson captured a world championship in a fourth division after shutting out fellow American Teofimo Lopez Jr to win the WBO junior welterweight title at New York's Madison Square Garden.
Stevenson, who won Olympic silver in 2016, frustrated his opponent with straight rights to the body, and held off Lopez's late counter-offensive with accurate shots from his left hand.
Southpaw Stevenson lost only one round on all three judges' scorecards as he took the 140-pound (63.5 kg) title by unanimous decision on Saturday.
The 28-year-old, who previously won WBO featherweight and super featherweight belts and the WBC lightweight title, became the 25th boxer in the sport's history to win world championships in four weight classes, as he improved to 25-0 in his professional career.
Stevenson then called out Conor Benn, who beat former WBA super-middleweight champion Chris Eubank Jr in November.
"We can get it banging, boy... I want the fight," Stevenson told Benn as they faced off in the ring.