Sir Alex Ferguson has warned Manchester United's Premiership title rivals never to write them off.

Substitute Diego Forlan's late winner cracked Southampton's stubborn resistance to earn United a much-needed victory.

Gordon Strachan's side had looked like holding Manchester to a third successive draw until Forlan popped up with his spectacular 86th-minute winner.

Ferguson said: "We are always capable of scoring and we will never quit.

"If teams want to get anything off us, they have to take it right down to the wire.

"This was a really important result for us, the kind of result which will hopefully see us pick up and start chasing the leaders," warned Ferguson who paid tribute to Forlan.

The Uruguayan ended his Premiership goalscoring duck against Aston Villa the previous week and came off the bench again to unleash an unstoppable dipping shot to break Saints' hearts.

Ferguson said: "He hit the shot perfectly but it must have dipped at the last moment because I thought it was going over.

The Saints boss admitted: "We lost because of one fantastic goal by them and a bad mistake by me.

"I felt my midfield players were dropping deeper and I wanted somebody in between them and the strikers.

"I thought we had weathered the storm - then they got that wonder goal.

"It's not often you feel really good about yourself when you leave Old Trafford.

"We have a good bunch of players here and while we are disappointed to lose at least they will be able to go home and tell their families they came here and gave it a really good shot."

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