Adonis Stevenson followed up his win over Britain's Tony Bellew by defending his WBC light-heavyweight title against Poland's Andrzej Fonfara.
Stevenson was knocked down in the ninth but got off the canvas to secure a unanimous points decision at the Bell Center in Montreal.
The 36-year-old (24-1) started the bout like a house on fire, putting Fonfara down in the first round and again in the fifth with a shuddering body shot.
But the Pole proved a brave opponent and came back strongly in the second half of the fight, catching the Haiti-born fighter with an excellent shot in a ninth round he dominated.
However, Stevenson rallied from the shock knockdown and had the better of the final three rounds to secure victory on all three scorecards; 115-110, 115-110 and 116-109.
It was the first time Stevenson, who now represents Canada, had been taken the distance since 2007, having stopped his opponent in his last 15 bouts.
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