A man has gone on trial accused of fatally punching a taxi driver in Dublin city centre, more than two years ago.
William Keegan of Pearse House, Pearse Street, denies the manslaughter of Moses Ayanwole on November 23, 2011.
The prosecution has described this as a "one punch case".
It is alleged that the accused man William Keegan struck Moses Ayanwole in the face during what appears to have been a minor dispute on Pearse Street in the early hours of November 21, 2011.
The jury has been told two students will give evidence that once the alleged punch was thrown the taxi driver fell back and hit his head off the pavement.
He lost consciousness and died in hospital two days later.
In his opening address on behalf of the prosecution, barrister Maurice Coffey described this as a "tragic and difficult homicide case".