Azeri heavyweight Teymur Mammadov has scored a controversial win in his Olympic quarter-final with Siarhei Karneyeu of Belarus.

Mammadov made the better start and took the first round 9-4, but was pegged back slighty in the second.

The referee then gave the Azeri a two-point warning for persistent holding, which gave Karneyeu two points to his total.

Another warning for the same reason came Mammadov's way in the third, at a time when he was barely able to stand up due to exhaustion.

An uninspiring bout was brought to a close with the Belorusian finishing strongly.

However, Mammadov won through on countback after the judges had scored the fight even at 19-19.