Signori put his side ahead with an acrobatic volley after five minutes, and he made it 2-0 similarly early in the second half with a low first time left-foot strike from 15 metres. The diminutive former Lazio forward turned provider in the 54th minute, setting up the midfielder Jonatan Binotto for Bologna's third goal, which made the quarter-final, first leg safe.
The Italians, who qualified for the competition via the Intertoto Cup and have not reached the semi-finals of a European competition since 1968, sat back in the final 20 minutes to protect their commanding lead ahead of the second leg in France in a fortnight's time.
A football agent told a French court yesterday that he helped Bordeaux with attempts to bribe referees with offers of gifts and girls before European competition matches in the 1980s.
Ljubomir Barin, a Croat, is one of four men on trial charged with fraud and bribery. The other three are the French club's ex-general manager, its former secretary-general and another agent.
At the continuing trial, Barin said he had offered his services to the then Bordeaux president, Claude Bez, who died last year, after the club "got robbed" by a refereeing decision in a European Cup match against Hamburg in 1981. After that he had received 500,000 francs (pounds 60,000) ahead of each European match to ensure there was no repeat. The court is trying to discover what happened to 4.2m francs pent by the club between 1983 and 1988.
Barin said yesterday: "Bordeaux would offer fur coats, shirts, gifts for the kids. Sometimes girls, I don't deny it. There were sometimes three or four of them."
But the club's former secretary-general, Herve Bizot, said the money was not meant to bribe referees but "to create a favourable environment around them".
France's two most famous referees, Michel Vautrot and Joel Quiniou, both testified it was the custom for referees to be offered gifts at European matches. But Vautrot said that was "after the games and in the presence of the Uefa delegate. They were gifts bearing the team's colours, nothing else."
Barin said no such practices took place any longer.
Celtic's captain, Tom Boyd, said he and his fellow defenders are desperate to keep Alan Stubbs at the club, although eh accepts that is the English centre-back is unhappy north of the border then it will be difficult for the club to persuade him to stay in Glasgow. Aston Villa are thought to be leading the chase for his signature.