United appeared to be on the receiving end of what would have been a third successive 1-0 defeat at Ewood Park after Paul Dickov had fired home a fine first-half goal.

Despite being reduced to 10 men as Lorenzo Amoruso picked up a second yellow card, Brad Friedel kept United at bay with a string of superb saves.

Eventually, with just 30 seconds of the four minutes of injury time remaining, Smith lashed home his fourth goal in five games after a clear handball by Louis Saha.

Afterwards Blackburn goalkeeper Brad Friedel criticised referee Alan Wiley.

An angry Friedel told Sky Sports: “It definitely bounced off Saha – I don’t need to see the replay, it happened right in front of me.”

“It seems every week we are talking about referees. We went down to 10 men, getting battered and then that happens,” said Friedel.

“It was one play [incident] on one day but it was a critical play. We were hard done by at Southampton and hard done by here. It’s not a personal attack on the referee. But we’ll take it, we’ve got a point, and we have to take the positives from it.”

United boss Alex Ferguson agreed it was handball by Saha. He said: “That’s another wrong decision by the referee today.”

Asked if he had sympathy for Blackburn manager Graeme Souness, Ferguson said: “I think Graeme will be quite happy he got a point – it could have been six or seven [goals for United].”

But the Scot conceded he thought United were going to leave Ewood Park with nothing.

“I thought we might go empty-handed. There are only a number of times you can hit a door and it doesn’t open. In fairness their goalkeeper must have made over half a dozen [saves].

“He did a fantastic job but we had some good chances and should have been putting a few away.”