Six Nations 2015: Return of 'wrecking ball' O'Brien boosts Ireland

The recent return from long-term injury of Lions flanker Sean O'Brien has boosted Ireland's chances of retaining their Six Nations crown.

The rampaging back-rower has endured a torrid time, recovering from shoulder surgery and an infection that forced him to go back to square one in his battle to regain fitness.

O'Brien's clearing out of three French players at a ruck in Ireland's victory in Dublin on 14 February has gone viral on social media.