United moved to the top of the Group B and closed in on qualification for the knockout rounds as Wayne Rooney's late header secured a crucial victory for the Reds.
Despite a much improved performance, it again looked like being another night of frustration for the team but Rooney - having earlier missed a sitter -steered home a 79th minute header from man of the match Jesse Lingard's cross as OT erupted with joy and relief.
United deserved to win but again made hard work of it- squandering several chances and almost being made to pay- Seydou Doumbia was thwarted by the block of the season from 'Mike' Smalling when he looked poised to score only moments before the decisive breakthrough.
Rooney almost scored in the third minute when he flashed a drive narrowly past the post, and then Juan Mata forced Igor Akinfeev into a fine save on 15 minutes after a superb pass from Daley Blind.
The Reds completely dominated the first half- both in terms of possession and shots at goal- but were guilty of missing genuine opportunities with Rooney's free-kick bouncing wide, Lingard lashing over the bar and Marcos Rojo's back-stick volley flying narrowly off target.
The second half started as the first had ended, with the Reds missing further chances to score.
Rojo nodded wide from six yards before a superb cross from the Argentinian picked out Anthony Martial, which the Frenchman could only direct straight at the goalkeeper.
Martial might have done better, his pace and energy epitomised United's improved display, but, with the 19-year-old tiring, LVG decided to turn to Marouane Fellaini to try and unlock the Russians' stubborn rearguard.
Memphis was also introduced and he crossed for Carrick to fire inches wide before the Russians best chance of the match fell to substitute Doumbia.
He forced an excellent save from De Gea with a well-struck effort on the counter attack, before the rebound- from the same player- was sensationally cleared off the line by the immense Smalling.
Then- finally- after 404 barren minutes, came the goal United had been threatening when Rooney popped up to power in Lingard's excellent cross to send a relieved Old Trafford into raptures and take us top of Group B.
Overall team performance: 7.5/10
Man of the Match: Jesse Lingard. The young winger produced a brave and combatic performance that means he just pips the impressive Bastien Schweinsteiger and Smalling as star man.