Zsolt Erdei remained unbeaten with a unanimous decision over Spain's Juan Nelongo Perez to retain his WBO Intercontinental light heavyweight crown.
Erdei took control in the eighth round when he landed two lefts and an upper right and put Perez in a corner.
The Hungarian was unable to finish off Perez, but managed to land a few more blows to the Spaniard as the round ended.
Erdei kept up the pressure in the ninth round with several blows just before the bell. However, he was nearly overcome by exhaustion and fought conservatively in the last three rounds. It was the first time he boxed past 10 rounds.
Two judges scored the fight 118-111 for Erdei, while the third had it 117-111.
Erdei acknowledged having little strength left in the later rounds.
"I've never been as tired as this and I can't really say why," Erdei said. "I'm so tired I don't even remember anything about the match.
"To be honest, I have a lot left to learn about my conditioning for the last rounds of a match."