Sir Alex Ferguson hailed Wayne Rooney's second-half strike as "phenomenal" following the 2-1 win over Newcastle.
Manchester United looked in danger of going four league games without a win after Darren Ambrose's opener, before Rooney and Wes Brown sealed the win.
Boss Ferguson said: "It took a fantastic goal from Wayne Rooney to change the pattern of the game.
"It was phenomenal - considering he was injured and I was getting ready to take him off."
Man-of-the match Rooney was struggling with a dead leg during the match, for which he received treatment after the final whistle.
Defender Gabriel Heinze was also injured during the game but intial fears he had broken his ankle have been discounted.
The Argentina defender was carried off after falling awkwardly following an aerial challenge with Shola Ameobi and was immediately taken to hospital for further examination.
United officials confirmed on Sunday night that X-rays had revealed there was no break.
Heinze will be examined at the club's Carrington training ground on Monday to determine the extent of the damage.
The result moved United to within a point of second-placed Arsenal in the league.
But the Gunners have a game in hand - against Tottenham on Monday.
Ferguson said a win was vital following a recent poor run of form.
"We hadn't won in four games and needed that win," he added. "And a win's a win when you're in a rough spell."
Brown, who scored the match-winner in the 75th minute, said he never felt like Manchester United would lose after they came out for the second half.
He said: "It was a tough game. They took the lead and we weren't showing anything.
"But I think we showed more belief in the second half. We passed the ball better and got forward - then we didn't look like we were going to lose."
Brown also said he was confident his side could now finish second in the league.
But he added: "We need to win the last games and hope that Arsenal trip up."