Willie Johnston, the Scottish footballer sent home from the 1978 World Cup in Argentina after failing a drugs test, has told how he feared he would be killed by armed guards who helped smuggle him out of the country.

Johnston, now 71, was flown back to Britain in disgrace after he tested positive for a banned stimulant following Scotland's shock opening defeat to Peru.

The substance -- Fencamfamin -- was in Reactivan, a medication prescribed for Johnston's hay fever. But he was taken from the team's training camp via a back exit and bundled in to a vehicle before getting on a flight out of Argentina.

Now, 40 years on, the Fife-born former footballer has recalled how he feared he would be shot dead before reaching the aeroplane.

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Speaking in BBC One Scotland documentary "Scotland ’78: A Love Story", to be shown on Wednesday, he said: "It was Archie Gemmell who came in and said 'you've to go for a drugs test. I took the drugs test and didn't think any more about it. I went back to the hotel.

"The next morning there were 100 people standing outside my room. I didn't know what was going on.

"I took two tablets called Reactivan. You could buy them in a chemist shop. I had hay fever and it was supposed to make me feel a wee bit better, but it didn't."

Johnston was driven away from the team hotel hidden under a blanket in the back of a vehicle, which was then met by armed guards. He added: "To get out the camp they said 'get in the back, lie down, we'll put the blanket over your head'.

"The guards came in with the guns and said 'up, up Johnstone. Up, up'. When I was on that bus on my own with two soldiers and two guns, I was thinking 'this is it, they'll take me to the end of the runway and shoot me'."

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On the flight home via Paris, he said he sat at the back of the plane but could read headlines about him in other passengers' newspapers.

He said: "It was in Portuguese or Spanish but this boy sitting next to me went 'that's you eh?', and I'm going 'yeah'. At Paris there were that many people coming on with cameras and journalists or film crew and I couldn't get peace."

Johnston never played for Scotland again. He said of his career: "I played for 22 seasons as a footballer and I enjoyed every minute of it, bar ten days in Argentina."

Bruce Rioch, who was captain of the 1978 World Cup side, tells the documentary: "We were absolutely stunned. Once that happened there were other discussions among the players and it came about that there was another one or two players had taken the same tablet."

Scotland went to the World Cup as the only home nation to qualify.

Manager Ally MacLeod famously believed his star-studded squad could win the tournament, and fans travelled to Argentina by any means they could find.

But they were defeated by Peru and drew with Iran, and a famous victory over eventual runners-up Holland couldn't prevent them from being eliminated.

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The hour-long documentary uses previously unseen footage, player recollections, and fans’ diaries and photos to chart the journey of the team and its followers.

MacLeod's widow Faye recalls how she felt for her husband as the team went from one disaster to another -- and the famously upbeat manager was pictured with his head in his hands on the sidelines.

She said: "I'll never forget when he was leaving he turned to me and he said, 'I'll either come back a hero, or a villain.

"I just wanted to fly out and give him a hug. Just seeing him looking so down, I thought 'that's not my Ally, looking so alone'.

"I was worried that he had no-one that he could talk to."

Commentator Archie Macpherson tells the programme: "When he put his head in his hands in despair, it was almost like a silent scream."

* Scotland ’78: A Love Story, is on Wednesday, June 6, BBC One Scotland, 9-10pm