Graham Gibbons' breath smelled strongly of alcohol on the day that horses ridden by him and Freddy Tylicki collided at Kempton, fellow jockey Jim Crowley has told a High Court hearing.
Tylicki is bringing a High Court claim against Gibbons over his fall during the 3.20pm race at Kempton Park racecourse in Surrey on October 31, 2016.
Tylicki was trampled after coming off his mount in the one-mile fillies' maiden race. He was left partially paralysed and is now a permanent wheelchair user.
The court earlier heard evidence from Jim Crowley, another rider involved in the race, who claimed he smelled alcohol on Gibbons' breath in the weighing room, but acknowledged under questioning there was no sign of him being "under the influence".
When asked about the allegation, Gibbons said it was "one person's opinion", adding: "There was 35 other jockeys in the weighing room on the same day - none of them smelled alcohol on my breath. If there was, the stewards would have been alerted."
In written submissions, Lord Faulks said Gibbons had previously received four drink-driving bans and he had not raced since December 2016 after being suspended when he "tried to pass off a urine sample from a young rider... as his own".
Asked why such details of his past were omitted from his written witness statement, Gibbons said they were "public knowledge" and he "didn't need to hide anything".
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Crowley also told the court that Madame Butterfly had been "clearly off the rail" during the race and disagreed with a suggestion from Gibbons's lawyer Patrick Lawrence QC that there was never "a sufficient gap for Tylicki to go through safely".
If Tylicki's court case is successful, his lawyers say an assessment of damages will be needed, with the claim "worth several million pounds".
His lawyers argue that Gibbons, who denies riding negligently, manoeuvred his horse Madame Butterfly into the path of Tylicki's mount Nellie Deen, which was running into a gap between his horse and the running rail at the edge of the track as they made a right turn on to the home straight.
They claim that Gibbons, who eventually won the race, must have known Tylicki was "up the inner" and if not, should have checked, before allegedly making the move that saw the horses collide and Nellie Deen fall.
The court also heard from another jockey in the race, Patrick Cosgrave, who told a stewards' inquiry afterwards that he thought Tylicki had been "ambitious" and "chancing it on a bit" during the race.
But giving evidence, during which video footage of the race was played, he said that "there obviously was room for him to go there".
Cosgrave said after the race he had tried to follow a "code of conduct" between jockeys and "not get involved" and tried to "stay as neutral as possible".
The hearing continues on Wednesday, when evidence is expected to be heard. Jim McGrath is to be called by Tylicki, while Gibbons relies on Charlie Lane.