Team Ballydoyle was last night adjudged to have deployed team tactics in the controversial renewal of the Juddmonte International Stakes at Newmarket last month. After a highly charged and occasionally stormy inquiry in London, Johnny Murtagh and Colm O'Donoghue, the two jockeys involved, were banned for seven days and Aidan O'Brien was fined £5,000.

More than four hours after they entered the building, the three men left the British Horseracing Authority's (BHA) headquarters without comment. O'Brien was ashen-faced, having stressed repeatedly throughout the inquiry that the concept of team tactics was anathema to all at Ballydoyle. “We would never want to win a race by default or cheating,” he said.

The panel ruled otherwise, although Tim Charlton, who chaired the inquiry, said that O'Brien's breach of the rules arose “from ignorance of his obligations” rather than any deliberate attempt at sharp practice. “We are not satisfied that he gave adequate, clear instructions [to Murtagh and O'Donoghue],” Charlton said.

Despite that, O'Brien will be furious at the slur on his name. As much could be gleaned from the series of heated exchanges he provoked with Graeme McPherson QC, acting for the BHA. Despite an admission from O'Donoghue that he was in breach of the rule, O'Brien's passionate defence of both his jockeys telegraphed his frustration at being summoned to the inquiry.

At one point he said to the barrister: “You are trying to make up a load of nonsense, Mr McPherson. I think the whole thing is a fantasy. I accept it if that's what Colm [O'Donoghue] said he did, but I don't agree with it. I just don't believe any of it...I'm so paranoid about [the question of team tactics] that I've probably told my jockeys about it a hundred times.”

O'Donoghue rode Red Rock Canyon, a pacemaker for the Murtagh-ridden Duke Of Marmalade, in the race in question. At the centre of the team tactics charge was that O'Donoghue deliberately manoeuvred his mount away from the rails, in the process ushering Murtagh through the gap and on to victory.

O'Donoghue was found guilty of “making a manoeuvre in the interests of another horse... from the same stable”, while Murtagh was adjudged to have behaved in a manner “prejudicial to the... proper conduct of horse racing.”

Both jockeys said that they were unaware of recent changes to the rules governing the use of pacemakers. O'Brien was effectively deemed guilty by association. All three can appeal within seven days of receipt of the official BHA notice, which is expected to be dispatched on Monday.

Before the hearing Murtagh agreed that the gist of comments he made after winning the race, and reproduced in The Sunday Times, were accurate. The most damning line comes when Murtagh instructs O'Donoghue: “When you get to the four-furlong marker, just ease off and give me a passage through.” However, Murtagh said yesterday that he had spoken when charged by adrenaline, and that there had been no such collusion.

At the time no action was taken by the Newmarket stewards even though the rule relating to pacemakers suggested that a breach had occurred.

The disciplinary panel is to release comprehensive reasons for reaching its verdict early next week, although Paul Struthers, the BHA's media relations manager, attempted to douse what are bound to be feelings of anger and injustice at Ballydoyle.

“In reaching their conclusions,” Struthers said, “the panel made it clear that there was no attempt to cheat; simply that the breaches occurred due to ignorance of the details of the rules in question.” O'Brien, for one, will not be placated so easily.