Darren O'Neill has become the first Irish boxer to exit the London Olympics after he was beaten by German’s Stefan Hartel in their middleweight round of 16 bout.

O'Neill entered the ring to rapturous cheers from a very vocal Irish contingent in the crowd, but it was the German supporters who had more to cheer throughout the fight.

The Kilkenny fighter was the busier in the opening stages of round one, but was finding it tough to break down Hartel's solid defence.

Hartel began to take control midway through the round, building off the back of his defence, and landing some mean looking body shots that helped him to a 6-4 lead by the end of round one.

O'Neill, aware he was trailing, took the fight to Hartel at the start of the second round. While he was getting through with some solid left hooks to the body, his offence was still overly reliant on going upstairs, which Hartel was defending with ease. 

The German continued to work behind his block and methodically picked off the more aggressive O'Neill with more some fine accurate punching, extending his lead to 14-8 by the end of the second.

The Kilkenny fighter went into the final round knowing that only a stoppage was likely to turn the tide for him and turned up the aggression.

Hartel, however, was happy in the clinch and looking to stay out of trouble. On the two occasions when O'Neill managed to back the German into a corner, he showed some clever footwork to escape and retake his position in the centre of the ring.

An increasingly desperate O'Neill began to lose his discipline, throwing wild haymakers with his right that were unable to trouble the German.

Hartel continued to stay out of trouble, picking off O'Neill who was leaving himself open as he sought the killer punch that wouldn't come.

In the end, Hartel shaded the final round 5-4 for a comprehensive 19-12 victory. Next up for the German is England's Anthony Ogogo in the quarter-finals.