Manchester United manager Sir Alex Ferguson was delighted with his side's vital win over Arsenal despite conceding they should have killed the game off more easily.

33973 - Fergie delighted to secure crucial victory

United needed Danny Welbeck's 80th minute strike to claim all three points thanks to a 2-1 victory, after Robin van Persie had cancelled out Antonio Valencia's opener on the stroke of half-time.

Ferguson believed United should have been more ruthless in the first half, but was proud of the way his side dealt with Arsenal's desperate late push for a second equaliser.

"We created an amazing amount of chances and to only score two is a bit disappointing," Ferguson told Sky Sports.

''We should have rammed home our advantage in the first half, and in the first 15 minutes of the second half they had three great chances and missed them all, so we rode our luck.

''When they put [Per] Mertesacker up and kept tossing the ball into the box, you never know what's going to happen but we coped well with that, Smalling was fantastic in that period and we managed to see it out.''

Victory was crucial after City earlier beat Tottenham 3-2 with Mario Balotelli's last-minute penalty and Ferguson added: ''Winning after City had won was the important thing but we've done it in the right way. We were really adventurous, positive and had a great belief in ourselves.''

Captain Patrice Evra agreed, adding: ''City won against Tottenham but we had to focus on ourselves, and it was a great win today.

''We are still behind City but we have to keep winning games. I am really confident in team, everybody is working hard and when we play with the Man United spirit, it is difficult to beat us.

''It was a good performance, we want everything perfect and in the second half there were 15 minutes when Arsenal played very well.

''We kept strong, had a good shape and scored a nice goal. We got the three points and that is really important if you want to win the title."