By Chris Bevan

Forest were on a high - they were up for it, we were going to the City ground and the game was on TV. The knives were being sharpened Mark Robins

There have been many goals for Sir Alex Ferguson to savour in his 20 years at Old Trafford - but only one has arguably saved him his job.

In January 1990, with United struggling in the league and trophyless in three years under Ferguson, the pressure was mounting on the Red Devils boss.

The FA Cup was his only chance of silverware - and seemingly, salvation - so the last thing he needed was a trip to high-flying Nottingham Forest in the third round.

If you believed the tabloids, defeat would have seen Ferguson sacked but in the end United triumphed thanks to a single goal by Mark Robins, a 20-year-old youth-team product made good.

Four months later United beat Crystal Palace in a replay at Wembley to lift the Cup - and the rest is history.

But would Ferguson have kept his job if United had lost that game?

"I have no idea," Robins told BBC Sport. "Nobody will ever know and I am pleased it never came to that and he was able to fulfil his destiny.

"He has made an outstanding contribution to football and to United. To have lost him there and for him not to go on to fulfil what he has done and achieved would have been a tragedy."

Robins vividly remembers the build-up to that game at the City Ground, which came after a run of seven games without a win in the old First Division for United.

"FA Cup games are always different, especially the third round," Robins explained. "It is a different sort of game and a break from the league, which that year we were not doing particularly well in.

"The players knew there was pressure on the manager because it was in all the newspapers.

"Forest were on a high and were flying. They were up for it, we were going to the City ground and the game was on TV. The knives were being sharpened.

He looked out for the young players and always had time for you, and you can imagine how busy he was Mark Robins on life under Sir Alex Ferguson

"In the end I don't think it was a very good game. It wasn't particularly memorable at the time but obviously it has lived long in the memory of other people."

Ferguson has never thanked Robins for his goal but, as a United fan, Robins is just pleased to have played his part in the club's most successful period.

"I wouldn't expect him to say anything," Robins said. "He gave me a job and I did it.

"There have been a lot more important goals scored for United since then - Lee Martin's goal that won him the Cup that year for a start.

"One or two things have gone on since then that eclipse my moment."

Robins - one of the original batch of 'Fergie's Fledglings' that included Martin and Russell Beardsmore, left Old Trafford for Norwich City in 1992 and played for 10 other clubs before retiring in 2005.

Now youth team boss at League One side Rotherham, he remembers Ferguson's arrival and the impact he had on the youth set-up at Old Trafford after taking charge in 1986.

"I had just arrived at the club myself aged 16, and from day one I felt included," Robins explained.

"It was just a knack he had. He learnt your names really quickly.

Bryan Robson and Ferguson celebrate United's 1990 FA Cup success

"That counts for a lot when you are a young lad at a club like that - and he was excellent.

"He looked out for the young players and always had time for you, and you can imagine how busy he was.

"City had a cracking youth policy at the time and Sir Alex wanted United's to be the best. He tried to change things and he was proved successful."

From Ryan Giggs to David Beckham and beyond, the list of young players that Ferguson has brought through the ranks in his two decades at Old Trafford is a long and illustrious one - and he has always taken a personal interest in their development.

"You know what he is like - you cross him and you are finished," Robins added. "But he has had to be like he is - he was trying to make players.

"He was manager and he had our respect. If you stepped out of line, in no uncertain terms you were hammered. It kept everyone on their toes.

"He put you under pressure but it was not about fear. It was a good learning environment and the way it had to be if you were going to end up playing for United."