Vitali Klitschko beat German challenger Manuel Charr by a fourth-round technical knockout in their bout in Moscow on Saturday to retain his WBC world heavyweight title.
The referee ended the fight after Charr sustained a cut above his eye, giving the man known as Dr. Ironfist the 45th win of his professional career.
Speaking immediately after the fight, Klitschko appeared to reject claims he would retire to concentrate on his career in Ukrainian politics.
"A continuation follows," Klitschko said when asked what would come next for him in televised comments.
"I'm disappointed I didn't manage to win the fight with a real knockout, just a technical one. Sadly, it's not our decision, but the doctor's decision. We wanted to continue the fight."
After a spectacular pyrotechnic entrance featuring a Zeppelin, Klitschko provided all the fireworks, sending Charr to the canvas as early as the second round.
The gulf in class between longtime champion Klitschko and Charr, in his first world title shot, was apparent from the start.
Charr boxed on the defensive throughout, keeping his guard up and attempting to frustrate Klitschko while landing few counter jabs of his own.
The second-round knockdown came from a right-hand shot, and, although Charr held steady in the third, the fourth round saw Klitschko land a choice combination to the German's head and then a left hook, leading to the crucial cut.
With blood flowing freely down Charr's face and chest, referee Guido Cavalleri ended the fight, enraging the man known as the Diamond Boy, who kicked at the ropes and launched into a defiant celebration of his own when Klitschko was proclaimed the winner.
The pair later reconciled and embraced.
For Charr, the defeat was his first in 22 professional fights. Klitschko has now won 45 of his 47 fights, with 41 wins by knockout and two defeats.
On the undercard, Russia's undefeated heavyweight Magomed Abdusalamov saw off Jameel "Big Time" McCline of the United States with a second-round knockout.
The American journeyman, 42, knocked Abdusalamov down within 30 seconds of the start, but the Russian recovered well and ended the fight with a stinging jab to McCline's face 1 minute 27 seconds into the second round that left the American sprawled on the floor.
The defeat was the 13th of McCline's career, while Abdusalamov continued his streak of knockout wins in all 13 of his professional bouts.