Six Nations: O'Mahony's past would have been known to Barnes - ex-Test referee Owens

Former international referee Nigel Owens says Peter O'Mahony's disciplinary record will have been known to Wayne Barnes, who sent him off as Wales beat Ireland in Cardiff.

O'Mahoney was dismissed after his arm hit Wales prop Tomas Francis at a ruck in Wales' 21-16 Six Nations win.

Owens, who took charge of 100 Tests before standing down form that level, told Scrum V Six Nations Munster's O'Mahony has previously been sent off for similar incidents, but became the first Ireland player to be banished in the tournament's history.

Watch more: Ireland 21-16 Wales highlights