A 90th-minute goal by Javier Hernandez gave Manchester United a thrilling 4-3 victory at home to Newcastle United on Wednesday that put Alex Ferguson's men seven points clear in the Premier League.
The leaders had to come from behind three times to win, and second-place Manchester
City's 1-0 loss at Sunderland meant that the traditional Boxing Day fixtures left United, without Wayne Rooney and Ashley Young due to injury and illness, with plenty of reasons to feel thankful.
City's loss at Sunderland was only their second defeat of the season and the result was rendered doubly damaging by events at Old Trafford. The champions threatened first when returning captain Vincent Kompany hit the bar in the eighth minute, but the home side claimed the game's only goal eight minutes into the second half.
Adam Johnson was the scorer, embarrassing his former City team-mate Joe Hart with a low shot from wide on the right that squeezed inside the near post.
Chelsea were also beneficiaries of City's slip-up, prevailing 1-0 at Norwich City through a 20-yard Juan Mata strike to close to within four points of Roberto Mancini's men with a game in hand.
Arsenal and West Ham United were the only Premier League sides not in action on Wednesday, after their scheduled game was postponed due to a strike on the London Underground transport network.