|Former United player Gibson (L) scores against Manchester City to give Everton an unexpected victory [Reuters]
It was not a sweet occasion for Premier League leaders Man City against the Toffees on Tuesday.
Darron Gibson's strike gave Everton a 1-0 victory over City and provided former club Man United with a vital boost in the title race to extend Everton's remarkable hoodoo over Roberto Mancini.
Gibson's first goal since his $790,000 move enabled United to go level on points with Mancini's league leaders and ensure City have now only one victory from their last 21 visits to Goodison Park.
The Republic of Ireland international's arrival earlier last month was not warmly welcomed by Everton supporters but this telling contribution could hand the initiative back to his old employers.
Goodison Park may have proven a pain for Mancini but City's struggles there have been even more frustrating over the years.
City always seem to come unstuck against the Toffees and again struggled with an Everton side who battled throughout and deserved the victory against a City side who failed to create chances.
Everton boss David Moyles was delighted by his team's hardwork and will also be celebrating signing in-form striker Nikica Jelavic from Rangers in a $8.6 million move.
Man United went level on points with their local rivals City after Javier Hernandez and Dimitar Berbatov converted a penalty each to give their team a routine 2-0 win over Stoke.
Hernandez slotted in from the spot in the 38th to put the hosts ahead and Berbatov added the second in the 53rd as an injury-depleted United took advantage of crosstown City's loss at Everton and now only trail the leaders on goal difference.
Stoke rarely threatened in a lackluster display as United goalkeeper Ben Amos comfortably earned a clean sheet on his Premier League debut, filling in for the injured David De Gea and Anders Lindegaard.
Gareth Bale scored twice and Luka Modric added another goal as Tottenham beat Wigan 3-1 to move within sight of the Premier League lead.
Bale's volley in the 29th minute was followed up by Modric's cool finish five minutes later from 18 yards to give Spurs a 2-0 half-time lead.
Bale struck again for his 11th goal of the season in the 64th, before James McArthur scored a consolation goal for Wigan in the 80th.
Coming off a draw against Wolves and a loss to Man City, Tottenham are now only five points behind City and Man United.
Spurs are also seven points clear in the final automatic qualifying spot for the Champions League from fourth-place Chelsea, who were held to a 1-1 draw at Swansea.
A last-gasp own goal by Neil Taylor gave Chelsea a point, as the Welsh club were narrowly denied another impressive home victory in the Premier League.
| Bale (L) of Spurs celebrates with Benoit Assou-Ekotto after scoring his second goal [GALLO/GETTY]
Scott Sinclair had given Swansea the lead when the former Blues winger volleyed the ball over Petr Cech five minutes before half-time after a poor defensive header by Jose Bosingwa.
Swansea, who stunned Arsenal at Liberty Stadium two weeks ago with a 3-2 win, looked set to take another big scalp when Chelsea defender Ashley Cole was sent off for a second booking in the 86th.
However, the visitors still levelled when Bosingwa's shot was deflected into the net by Taylor in injury time.
Having advanced in both domestic cup competitions in the past week, Liverpool got their Premier League campaign back on track with a 3-0 win at Wolves.
Out-of-form striker Andy Carroll scored his first league goal since October 29 , Craig Bellamy added another in the 61st and Dirk Kuyt wrapped up the scoring in the 78th as Liverpool had just their second win in the past seven league matches.
Liverpool are now only four points behind Chelsea in the final qualifying spot for the Champions League.
The Reds reached the League Cup final by knocking out Man City last Wednesday and beat Man United to advance to the fifth round of the FA Cup on Sunday.