Brendan McGoogan told the trial of a man accused of murdering Elaine Doyle at the High Court in Edinburgh that he must have been watching Canada play France on June 2, 1986.
The 16-year-old's body was found the following morning near his then home in Greenock, Inverclyde.
The court heard that Mr McGoogan, then a student, was at home for the final part of the match in which French player Jean-Pierre Papin scored after 79 minutes.
Mr McGoogan, now a Swiss-based IT and banking consultant, was then a student and living directly opposite Ms Doyle's home, the court heard yesterday.
Mr McGoogan, 47, told the court he did not hear or see anything suspicious at around the time Miss Doyle should have arrived back in the town's Ardgowan Street after a disco.
He was giving evidence at the trial of John Docherty, 49, of Dunoon, who denies murder and has given a list of 41 possible suspects who, he says, might include the real killer.
Mr McGoogan told the court had been out that evening himself before arriving home. Mr Docherty's QC Donald Findlay produced match statistics which helped place Mr McGoogan in Ardgowan Street.
The trial continues.