Cardiff Blues have revealed Wales scrum-half Tomos Williams played a crucial role in the derby win against Ospreys in between celebrating his older brother's wedding.

Williams was an usher at the wedding before driving to Swansea to play rugby and returning to the reception in Treorchy.

The 24-year-old created the Blues' only try in the 19-16 win.

"That's what rugby means to him," said head coach John Mulvihill.

Williams was one of three Blues players yellow-carded in Swansea with his transgression being a high tackle on Ospreys flanker Dan Lydiate which ended in a penalty try for the hosts.

The Wales number nine was a controlling forced in the second-half comeback and his deft chip provided the chance for Jarrod Evans to score the Blues' only try.

This was despite the pre-match disruption with the match kicking off at 19:35 GMT.

"Tom wasn't at the pre-match meeting and he wasn't on the bus travelling down," said Mulvihill.

"He arrived here (Liberty Stadium) at six o'clock. He was an usher at his brother's wedding in the afternoon, came and played his game and went straight back there.

"He didn't want to miss this game or the wedding.

"It was a fantastic effort. That's what this club means to him. He is a real competitor who wants to play every minute in every match, and he's played some good ones for us here."

Mulvihill believes Williams' form could lead to a starting spot in Wales' 2020 Six Nations opener against Italy on 1 February where he will face competition from World Cup first choice scrum-half Gareth Davies.

"The other boy is pretty good but in the World Cup Tom went on and changed games," said Mulvihill.

"They (Wales) wouldn't have beaten France (quarter-final) if he hadn't got in there, put pressure on and ripped that ball.

"He adds a spark every time he plays and brings the best out of the people around him.

"We think he's number one, he thinks he's number one, but we'll just wait and see."