Mr Vowles, 29, won the right to a massive payout from the WRU in a landmark ruling last December.

He had already received the maximum insurance payout of �91,000 - but the court ruling meant the cash-strapped WRU would be liable for millions of pounds in compensation.

No amount has so far been set, but similar cases have resulted in seven-figure sums. The hearing is expected to last two days.

The former hooker from Llanharan, south Wales, broke his spine playing for his village side in January 1998, and has been left dependent on a wheelchair and the help of relatives.

At the High Court in London last December, the WRU admitted responsibility for the match referee's failure to opt for uncontested scrums, which caused the collapse.

Usually, if a side is forced to field players without experience in the front row of a scrum the referee will allow uncontested scrums - reducing the risk of injury.

Richard Vowles broke his back

It was the first time an amateur referee in any sport has been held liable for injuries in an adult amateur game and will have "horrendous consequences" for all sport, according to the WRU.

The ruling appears to make governing bodies responsible for duty of care on the field.

The level of damages has not yet been set. Lawyers for the WRU and the referee are considering appealing the decision.

Former Commonwealth Games boxer Mr Vowles had taken up boxing professionally just prior to the accident, which happened in the match between Llanharan's second XV and that of local rivals Tondu.

Training

He claimed referee David Evans - a solicitor - broke the rules when he allowed a scrummage to be weakened by inexperienced players in bad weather conditions during the game's final seconds.

He did not ask whether Mr Vowles - who had expected to be a reserve front-row substitute - was trained to play at hooker.

On a muddy surface, the scrum collapsed, severely injuring Mr Vowles' spine. He has used a wheelchair and has required 24-hour care from his father and others since the incident.

Judge Mr Justice Morland said Mr Evans' decision was in breach of his duty to take reasonable care for the safety of the front-row forwards.

Vowles boxed at the Commonwealth Games

Mr Vowles - to whom the WRU gave a maximum insurance payout of �91,000 after the accident - had established that, on the balance of probabilities, this breach of duty was a material cause of his accident.

The WRU accepted "vicarious responsibility" for the referee's decision. Llanharan RFC was not found negligent.

In similar cases, damages of millions of pounds have been awarded.

WRU chairman Glanmor Griffiths said at the time : "We are concerned about the judgement... and the implications of the decision for the game of rugby union.

'Highest standards'

"Each year the union invests heavily in player, coach and referee education and puts the safety of players at all levels as a number one priority.

"In addition, the union is able to boast some of the highest standards of refereeing in the world game."

Mr Vowles said: "I am just glad to get it out of the way.

"This is going to make a big difference to my life. This ruling is going to make the game safer for everybody else."

His lawyers said the decision was of "great significance for the game of rugby union in particular and contact sports in general".

Solicitor Phillip Griffith said: "Whilst money can never compensate for the tragic injuries he suffered at such a young age, it will make life a little easier for him.

"The decision is also very significant for the game of rugby generally .. [it] extends the principle that referees owe a duty of care to players in a rugby match to adults, whether amateur or professional."