It is now 17 years since one of the darkest days in club history: Clyde 2-1 Celtic.
The Bully Wee sensationally bullied Gordon Strachan's side - including two debutants in former Manchester United and Republic of Ireland midfielder Roy Keane and Chinese defender Du Wei, making his one and only 45-minute appearance for Celtic at the time - out of the tournament with a monumental 2-1 giant-killing act in the third-round tie at Broadwood.
Goals by Craig Bryson and Eddie Malone were enough to send the then First Division side through despite Celtic grabbing a late consolation courtesy of Polish striker Maciej Zurawski.
In actual fact the hosts managed to have the ball in the net twice early on - but both efforts were ruled out for infringements before Bryson stooped to head home the opener on 33 minutes.
Four minutes later Malone crashed home a spectacular volley following a flick-on at a corner kick merely seconds after Celtic goalkeeper Artur Boruc had spectacularly turned Stephen O'Donnell's penalty kick around the post.
For Malone, it was his greatest career highlight... but also the scene of his biggest regret. The former was because of his stunning goal, the match-winner and difference between the sides in the end. The latter, the regret, because he should have bagged a coveted football trophy in the shape of Keane's match shirt. He didn't get it.
"I hit about 20 goals in my career and most of them were either headers or free-kicks, I never scored many like that from open play," said Malone, now a youth and community coach at Spartans. "It is a career highlight scoring a screamer to beat Celtic but it is also one of my biggest regrets.
"I went back out to celebrate with the Clyde players. I should have man-marked him in the tunnel and got his shirt. I had asked Roy Keane for his jersey at full-time when I shook his hand and he promised he would give me it in the tunnel after the game. With everything that was going on, I ended up celebrating for half an hour on the pitch after the game.
"Celtic packed up and got up the road on the bus sharpish and I didn't see him. That is my only regret from that day that I did not get Keane's Celtic jersey as a souvenir. I still think about that every day and I say to myself 'what was I doing?' I still wonder where the jersey is. I wonder if Keane kept it."
Keane had a debut to forget but Du Wei, well, he had a bonafide nightmare and was never seen again in a Celtic jersey. It was a cup shocker of seismic proportions as Graham Roberts and Joe Miller's men, who had an average age of younger than 21, did the ultimate number on the Hoops and more than deserved their win.
Malone recalls how the players received a massive bonus of £2,000 a man for beating Celtic - and that the squad were on the same amount for both the win and a draw on the day.
"It was weird because the Clyde board set the bonus as the same amount for a win and a draw," he said. "I think they wanted to take the tie back to Celtic Park for a money-spinner. That never really entered the boys' heads, to be honest, but we all got £2,000 a man and that was double our monthly wage. Winning was a real bonus to the club both in terms of prestige and finance.
"Everything seemed to go right for us on the day. We were a young, hungry team. We had no stars on the side and we all had something to prove. Most of that team went on to enjoy decent careers. Bryson got capped for Scotland. Tom Brighton signed for Millwall and most of the other players played in either the SPL or First Division.
"I don't remember being put under too much pressure either in terms of kicking the ball off the line or being under the cosh which is rare when you play Rangers or Celtic. Even when Zurawski scored luckily for us we never got the expected late onslaught luckily for us."
Malone admitted that it was the good cop/bad cop management team of Miller - who scored the winner in the 1989 Scottish Cup final for Celtic - and former Ibrox defender Graham Roberts that convinced the Clyde players that the Hoops were there for the taking.
"Graham was the one that would go absolutely mental and Joe was the one that would get us all back onside after Graham's rants," Malone recalls. "The pair of them were good together.
"Graham had gone to watch Celtic the week before against Hearts at Tynecastle and Stiliyan Petrov got injured. He told us that their best player with all the legs was injured. He told us that the rest were all finished. The likes of Neil Lennon and John Hartson were all older and coming to the end of their careers and we were all embarking on ours... he told the Clyde players to go out and have a go and get at them.
"He convinced us that we had a great chance and that's exactly how it panned out. That was Graham's sort of style as most of us had been released by other clubs that summer but he kept telling us 'you don't know how good you are' and told us all that we could play at a higher level, we just needed to go out and prove it. Both Graham and Joe gave a lot of those players some belief back. We went out that day against Celtic believing and feeling that we could beat anybody.
"The number of times that people send me a clip of my goal, I don't ever need to seek it out on YouTube or whatever. I get tagged in that kind of stuff all the time. I never enjoyed video analysis because when I watched the English Premier League on TV and then I watched myself I always thought 'by God, that's shite!'
"But it crops up every year around this time so it is a wonderful career memory. I would not swap it. I was relegated at Ayr United and that was horrible so you have to enjoy the good times and the good stuff when it comes along."
Malone's fellow goalscorer Bryson went on to represent Scotland three times as well as turn out for the likes of Kilmarnock, Derby County, Aberdeen and St Johnstone. He readily admits that beating Celtic in 2006 was the game that put him on the football map.
"It was the game that changed my career, just a little bit," Bryson said. "I cannot believe how long ago it was. It was incredible, from a Clyde point of view, just to be drawn against Celtic but to beat them was something else.
"I think everybody forgot Celtic were actually playing Clyde in the run-up - it was all about Roy Keane and how they'd win because he was making his debut. We were forgotten about so we just got on about our business quietly and effectively. The end result showed.
"Graham and Joe told us that we had nothing to fear as we were a young team. When you look at the age and experience of the two squads it is no wonder that this match is still seen as a massive win for Clyde and still talked about as one of the biggest Scottish Cup shocks to this day, if not in the tournament's history.
"When you are younger there is an element and attitude of you don't care who you are playing against. That takes the pressure off a bit - and there definitely was a wee bit of that.
"There were still nerves as this was the biggest game for every Clyde player in the dressing room as we were playing Celtic and it was on TV and your direct opponent was Keane. Once the game started all the nerves disappeared and we got right into it. We just felt that we had nothing to lose and all the pressure and spotlight was on them.
"I grew up a Celtic fan so to score against your boyhood idols and to win against them in the Scottish Cup was a great experience - the stuff of dreams, you never actually believe it will happen.
"It was a good finish with the head actually and, as a midfielder, I was always gambling by going into the box. Eddie slung over the cross, Boruc missed it and I managed to steer a header into an empty net. Thankfully I have a better haircut now though!
"Clyde were going well in the league at that time so we knew we could give a good account of ourselves. I don't like to criticise fellow professionals but Tom Brighton and Alex Williams gave Du Wei a torrid time in that game. He was never seen in a Celtic jersey again after that and I imagine Gordon Strachan was raging.
"We had three goals disallowed in the game - including one from myself in the second half - and even when Zurawski scored to make it 2-1 there was that feeling that Celtic would go on and win and that Clyde had got their bit of luck and had their fun but it was all going to come to an end. Surprisingly, we were very comfortable in the game."
Did Bryson, as his direct opponent, exchange any words with his legendary adversary Keane in the midfield area on the day?
"It was business as usual with Keane really," he said. "I am not the kind of person that likes to have conversations with opposition players on the pitch. You do anything you can to win and talking to your direct opponent is not one of them.
"You could tell on the day he was still a quality player. I don't know if he struggled by coming to Celtic and not playing alongside the quality of player that he was used to or Keane maybe did not know what to expect on his debut at Broadwood and thought that he had to turn up and beat us without him actually saying that. I am not sure he was the problem on the day though as Celtic didn't turn up. Fortunately for Clyde, we turned up, Celtic had an off day and we took our chances."
Unlike Malone, at least Bryson was savvy enough to grab a Celtic jersey at the end.
"I got Aiden McGeady's shirt," he confirmed. "I don't even think I swapped shirts with him because I don't imagine he'd have wanted a Clyde jersey or a reminder of a day like that. I still have the jersey to this day. I played with Aiden at Queen's Park, he is a nice guy and, despite the result, he still had the decency to give me his top."
Some 17 years on those reminders remain as clear, sharp and stark in the memory of an unforgettable day for the men from Cumbernauld.
What were they called? Clyde. Just ask Gordon Strachan, Roy Keane and Du Wei their thoughts on the Bully Wee.
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