In a highly entertaining bout that swung one way and then the other, the two fighters mixed full-on trading with cagey tactics as both looked to put themselves in with a chance of a world title shot.
The early exchanges went to Donaire as Darchinyan struggled to gain a foothold in the first two rounds, although the third and fourth where much better for the Armenian as he hurt the Filipino with some telling punches.
The next four rounds could have been argued for either fighter as the two had no problem mixing it up in the centre of the ring, with the fight on a knife-edge entering the ninth session.
Midway through the round and Donaire unleashed an almighty shot that dropped Darchinyan hard and the 37 year-old was all over the place upon getting to his feet.
Referee Laurence Cole gave Darchinyan the benefit of the doubt and allowed him to fight on, but it was just a matter of time and Donaire pounced to gain the timely stoppage as the round drew to a close.
It was a much-welcome return to form for Donaire, who lost for the first time in over a decade last time out against Guillermo Rigondeaux, although ‘The Filipino Flash’ looks vulnerable and easier to hit since returning from the loss.
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