Arsenal boss Arsene Wenger is confident victory over Manchester United will prove a significant performance in the development of his young team as they look to end the club's trophy drought.
From the starting XI who won Wenger's last trophy - the FA Cup in 2005 - only Cesc Fabregas was in the side that defeated United 2-1 in a gripping clash at the Emirates Stadium.
There were doubts whether Arsenal had the resolve for a Barclays Premier League challenge but Samir Nasri's double breathed life into their campaign after dropping points recently to rivals Tottenham and Stoke.
''It was a very important result because I imagined what would have happened if we lost,'' said Wenger, whose side overtook United in the table.
''Mathematically, it was key to stay with the top and show determination, spirit and mental attitude.
''I knew today that was a big game for the future of the team. To keep in the race, you need to win big games like that - and it is vital for a young team.''
Wenger himself has been questioned by a small minority of fans, although his name was chanted during this victory.
''I can take criticism,'' the Frenchman added. ''I am in a job where you have to take that. There is only one answer - with your performance on the pitch.
''I didn't doubt the spirit of my players. We made mistakes but I didn't question the spirit, quality or ability to play for the championship.''
Nasri opened the scoring when his half-volley flew in off Gary Neville, then he added the second after Cesc Fabregas had found him in space on the edge of the area.
Fabregas told Sky Sports: ''It has been frustrating, with the results we have had - and to win a game like that is vital, to get back on track, we were talking about it the other day.
''When you see the fans singing and enjoying themselves, this is the best we have had this season.
''But because we have beaten Manchester United, we are not better than we were last week - and last week we were not rubbish as everybody was saying.''
Rafael da Silva came off the bench to score and set up a thrilling final six minutes of injury time - but Arsenal held on for the win they needed.
''We went out to win no matter what happens,'' Wenger said.
''It's a team answer - we showed that we have the squad, and that has been questioned. We showed that no matter who plays, we have the spirit.''
United boss Sir Alex Ferguson called it ''fantasy football'', while Wenger added: ''It does not matter if you love Manchester United or love Arsenal. It was a game for people who just love football.''
After the final whistle, skipper William Gallas was the last off the pitch as he celebrated with fans.
The skipper said: ''It was really important for us to win against Manchester United, because we want to stay in the race - to do that we want to win every game.
''The last few games we have drawn and lost, so it was important to win at home.''
Wenger felt Gallas was not the only leader he had,
''You need a shared leadership on the pitch - five or six on the pitch,'' he said. ''We had 11 leaders on our side because everyone took initiative at the right time.''