Duncan Ferguson became first British player to be jailed for on-field incident but he wasn't booked by referee

Duncan Ferguson became the first and only professional player in Britain to be jailed for an on-field offence when he headbutted an opponent in 1994.

More than three decades ago, the towering striker made headlines when he landed a headbutt on defender John McStay during a Scottish Premiership clash between Rangers and Raith Rovers.

Kenny Clark, the referee, had been looking the other way and didn't give a card.

But the flattened McStay was left with a cut lip and Ferguson was later convicted of assault at Glasgow Sheriff Court after losing his appeal.

In total, he was sentenced to three months in jail, with the prison sentence being his third conviction for assault.

As well as being banned for 12 games by the Scottish Football Association, he served 44 days in the city's Barlinnie prison before being released.

Years later and the former Everton striker, who was playing for The Toffees at the time of being jailed, claimed he should not have been made an example of and described the headbutt on McStay as "nothing".

Speaking to Everton fan channel Toffee TV in 2019, Ferguson opened up on the incident.

"It was wrong me being there, it wasn't fair," he said. "I shouldn't have been in there and I think a lot of people understood that. It's not as if I was in for doing anything bad really. My God, it was nothing.

"The fans got me through it, a lot of them wrote to me. It was unbelievable all the letters and the support that I got."

Ferguson added: "I got all the letters when I was in there and obviously you have got a lot of time on your hands when you're in there to read through them all.

"It definitely gets you through it and you never forget those things."

Back in 2019, McStay also spoke about the Ferguson headbutt incident during an interview, where he opened up about his battle with depression following the clash in 1994.

"No one knows I had it [depression]. No one apart from my wife really knows," he told The Scotsman.

"I was on medication for 18 years. It changed me, put it that way. I am not blaming the headbutt. Things happen in life. Getting divorced as well.

"I stopped playing football at the same time. Everything just happened. Things happen in life you cannot handle. But I lost a bit of belief, hope. I could not handle not being at Raith Rovers anymore.

"That's the thing, I was only 28 when it happened - it felt as if I was maybe in my 30s, at the end of my career. I was only 28 and that was it. Done."