Wilson, 26, of Edinburgh, is accused of attacking Mr Lennon, aggravated by religious prejudice, at a crucial Celtic v Hearts match on May 11 this year.

Mr Church, 54, a former Strathclyde Police officer, said: "The atmosphere was tense - very tense.

"Normally Celtic v Hearts games are high-profile games. There's not a lot of love lost between the two sets of supporters so there's usually a bit of an atmosphere.

"But this particular evening I would say the atmosphere was worse."

Mr Church said that Celtic were locked in a race to win the Scottish Premier League title, which they subsequently lost.

However, at that stage in the season there was still all to play for, and the points from that particular tie were crucial.

He added: "Right from the start the atmosphere was pretty bad. Lots of vitriol being directed towards us.

"They were being quite aggressive, shouting towards us, although not from the ones directly beside us but you could hear things coming from just beyond that - some quite unpleasant things."

When asked how many fans were shouting, Mr Church replied "most of them, to be fair".

Mr Church said he was sitting in a row of seats just behind the dugout, where Mr Lennon and the rest of the management were sitting with the team substitutes.

To his left were three match stewards, however he said he became so concerned about the vitriolic atmosphere during the first half that he made a phone call to the security control room, where the Hearts safety officer and the police officers sit, calling for more stewards and police officers in the stand.

He said: "I would have liked another two or three stewards and perhaps a police officer. I was getting quite concerned."

When asked whether his concerns were listened to, he replied: "Well, nobody arrived."

Mr Church said the atmosphere worsened immediately after the second goal.

He said: "I would describe it as poisonous. I was getting quite concerned because we had just scored a second goal and they (the Hearts fans) were getting quite angry."

Wilson denies attacking Mr Lennon by lunging at him and seizing him around the neck, aggravated by religious prejudice.

He also denies committing breach of the peace by conducting himself in a disorderly manner, running out on to the field of play, shouting, swearing, and making a sectarian remark to the annoyance of others.

Several of the jury of eight men and seven women at Edinburgh Sheriff Court disclosed that they had either watched the game on television, or had prior knowledge of the allegations through the press.

However, given the high profile of the alleged victim, Mr Lennon, the judge was satisfied that this would not impede the trial, which continues this afternoon.