Jon Hiles represented the Great Britain roller hockey team
A student accused of killing a teenager in a Greek nightclub has begun a High Court challenge against a ruling that he must be extradited to the country.
Jonathan Hiles, 18, of Llandaff, North, Cardiff, died after being pushed off a nightclub stage in Zakynthos in 2007.
Andrew Symeou, 20, from Enfield, north London, is accused of manslaughter. He denies any wrongdoing.
Lawyers for Mr Symeou insist the case against him rests on "fabricated, tainted and manipulated evidence".
Two High Court judges were on Thursday asked to overturn an extradition decision made by a district judge at Westminster Magistrates Court in October.
Mr Symeou was on a Club 18-30 holiday with friends Charles Klitou and Chris Kyriacou when Mr Hiles died.
Edward Fitzgerald QC, representing Mr Symeou, said there was evidence that Mr Klitou and Mr Kyriacou were punched repeatedly and verbally threatened to coerce them into making statements incriminating Mr Symeou.
There had also been manipulation by the police of statements made by Mr Hiles's friends, with a number of them giving word-for-word identical statements, the court was told.
Mr Fitzgerald said: "This justifies the conclusion that it is an affront to justice to permit an extradition based on such evidence to proceed because the stream of justice has been polluted at source."
Andrew Symeou has always denied responsibility for the death
Mr Hiles, who represented the Great Britain roller hockey team and also played ice hockey for Cardiff Devils' junior team, was fatally injured on 20 July 2007.
Mr Symeou, a Bournemouth University student, said he did not know about Mr Hiles's death until his return to the UK on 24 July 2007.
He was then arrested under a European arrest warrant (EAW) on 27 June 2008.
Mr Symeou's extradition is being sought by the Public Prosecutors' Office in Patras.
Peter Caldwell, appearing for the Greek prosecutors, told the judges if investigations revealed that evidence from Mr Klitou and Mr Kyriacou had been obtained through ill-treatment it would not be taken into consideration.
He said that, even if that evidence was excluded, there was other evidence capable of establishing the guilt of Mr Symeou.
The judges reserved their judgment and are expected to give it within the next few weeks.