David Lemieux scored a very heavy knockout win tonight over Gary ‘Spike’ O’Sullivan in their grudge middleweight bout in Las Vegas.

The fight promised fireworks from the start given not just for the needle between both men in the build-up but also their exciting fight styles.

Both guys liked to come forward and throw big bombs and tonight that style went the way of Canadian Lemieux.

He took out Gary ‘Spike’ O’Sullivan in the very first round.

Here is the moment that it happened as the much heavier Lemieux ended proceedings tonight:

Here is another angle of what was a huge shot to close the fight in the end:

Lemieux still clearly carries massive power at 160lbs and that win makes the boxing display Billy Joe Saunders put on last December to shut him down look all the more impressive.

Indeed, judging by Lemieux’s post-fight interview it is a fight that still haunts him.

Hard luck to the well liked O’Sullivan who did something that few Irishmen have ever achieved tonight in fighting on such a big card in Las Vegas.

As for Lemieux, all credit to him.

This win puts him back in the middleweight picture again with no doubt some significant fights in store next year.