Each time I shout, and the rhythm of it, as the dogs' energies start to fade, becomes regular - a chant - as we tribe of men call for death.

Finally, Red, who I can now see has more energy and has sustained fewer wounds, twists his head under Black's tired lunge and secures his jaws around the other's throat. He grips and shakes, driving his teeth deeper. Black gives a piercing howl but Red continues, blood running out over his muzzle and down onto the floor, pooling there.

Black's struggles slowly subside and Red follows him down to the floor, his teeth still clamped, as his opponent's legs twitch with slower and slower frequency.

The noise in the room grows to a frenzy of celebrations and curses as the attention moves from the ring to the collection of bets, but my eyes don't move from the dogs. Red has allowed his legs to collapse beneath him, but his jaws are still fastened to his dead opponent as if daring him to rise again. A man moves aside the box nearest to me and approaches this tableau, prising Red's jaws open and fastening a further length of red rope to his collar. Then, pulling the dog to his feet, he leads the victor from the ring. No-one moves to collect Black's body. Whoever has organised tonight's event will probably take the body and sell it. There's some good meat on a dog of that size that somebody would be happy to pay for.