Arsenal overcame one of the most controversial goals of the season in a 2-1 win against Everton.
Fabregas row puts Arshavin and Koscielny goals in the shadows
Arsenal displayed the battling characteristics of potential Premier League champions as they overcame one of the most controversial goals of the season to defeat Everton at Emirates Stadium.
The performance of Lee Mason will be under scrutiny after the match referee allowed Louis Saha's hugely-debatable first-half opener to stand, while he also brandished eight yellow cards in total.
But of greater long-term significance to Arsenal and manager Arsene Wenger will be the fact that goals from substitute Andrey Arshavin and centre-back Laurent Koscielny ensured the Londoners remained in pursuit of Manchester United.
A 3-1 win over Aston Villa at Old Trafford maintained United's five-point lead at the top of the table, but the second-placed Gunners will deservedly keep a genuine belief of securing a first Premier League trophy since 2004.
The defeat was harsh on a well-organised Everton, who, despite a lack of a genuine cutting edge, had matched their hosts for the majority, with Marouane Fellaini and Jack Rodwell winning the midfield battle.
But a 13th defeat in their last 15 Premier League visits to North London means that David Moyes' team remain in trouble at the wrong end of the table with just 27 points from 24 games.
The match had started with a bang. Jack Wilshere's yellow card inside the opening five minutes for a naive challenge on Mikel Arteta was an act of frustration from Arsenal's teenager, who was coming under close attention from the superb Fellaini and Rodwell, and it provided a snapshot of the first half.
Feisty
Wilshere was not being allowed any time to settle and his battle with Rodwell, who he is expected to partner as first-choice selections in England's midfield over the coming decade, was fascinating viewing.
The midfield was proving a feisty area. Arteta broke forward and Arsenal captain Cesc Fabregas, who was later accused by Moyes of using 'disgusting' language when addressing Mason at half-time, was fortunate not to follow Wilshere into the book when raking his studs down the heel of his fellow Spaniard.
Moyes had named the same starting XI to that which drew with defending Premier League champions Chelsea in the FA Cup at the weekend and had clearly told his players not to allow room for Arsenal, who started with Tomas Rosicky in place of the injured Samir Nasri.
Fellaini's powerful presence was making Wilshere and Alex Song look like rag dolls, but Everton, having watched on in probable amazement at the actions of city neighbours Liverpool on transfer deadline day, were also adding finesse to their muscle with efficient one and two-touch passing.
The 15th minute brought a first real threat from Arsenal, who also spent Monday watching derby rivals, Chelsea in this case, spend huge amounts of money.
Sylvain Distin saw yellow for scything down the advancing Bacary Sagna on the right-hand side of the Everton box, Robin van Persie's resulting free-kick deflected for a corner and Koscielny headed just a few feet wide.
Koscielny's header seemed to bring Wenger's men to life and Fabregas was allowed to get goal-side of Everton's midfield enforcers, but Tim Howard in the visiting goal was still to be tested.
Theo Walcott, who had been anonymous in the opening 20 minutes, soon addressed the Everton shot-stopper's inactivity, collecting a loose ball after a half-hearted John Heitinga challenge and forcing a save with the legs.
Saha, though, then struck to an explosion of fury in the 24th minute. The Frenchman held his run in anticipation of Seamus Coleman's pass, but, when the dinked delivery arrived, Everton's No.8 had drifted two or three yards offside.
Arsenal's defenders were screaming for a whistle, but a deflection from the swinging boot of Koscielny was presumably deemed to have changed the phase of play amid the general confusion of the offside rule, and referee Mason, having consulted with his assistant, Stephen Child, allowed the goal to stand.
The majority of the 60,000 attendance at Emirates Stadium let Mason know what they thought of the decision, while Fabregas set about attempting to restore parity with a driving run forward before shooting just wide when under pressure from Rodwell.
Outrage
Van Persie collected a glorious pass from Wilshere on his chest, but, in scooping his half-volley over the advancing Howard, Arsenal's Dutch superstar applied too much power to also clear the crossbar.
The first half ended as if it was full-time in an end-to-end cup tie and Everton should have scored another through a wasteful Diniyar Bilyaletdinov prior to Mason's whistle, which brought a cacophony of boos from outraged Arsenal fans.
Abou Diaby was introduced by Wenger at half-time to possibly add a physical presence in his midfield, but Cameroon international Song had also taken a few crunching knocks in the first half.
Moyes had clearly let his players know that he wanted more of the same against an Arsenal team who had looked a little jaded in the wake of a record nine matches in all competitions in January, including Sunday's FA Cup win over Huddersfield.
Rodwell could quite easily have seen a red card for leaving the ground with two feet and impacting around Walcott's shins, with Arsenal's players continuing to protest that they were on the wrong end of Mason's decisions.
The Gunners, wary that they had already lost at home to West Brom, Newcastle and Tottenham, were in danger of allowing their sense of injustice to get the better of them, but a deflected effort from Gael Clichy almost brought the equaliser they craved.
As the hour mark edged into view, Arteta was booked for an almost identical tackle on Fabregas to that which he had received from his compatriot in the first half. Van Persie soon followed following a spat as the match's sixth yellow card.
The game was in danger of boiling over. Wenger decided to replace the passenger of Rosicky with Arshavin. Moyes brought on Leon Osman as Bilyaletdinov's evening came to an end.
Everton's superbly organised midfield was dropping deeper as a bank of five and, after Diaby flashed a shot well wide, Wenger added to his attacking options with the introduction of Nicklas Bendtner as Arsenal's last remaining change.
However, it was substitute Arshavin who was to score the equaliser in the 70th minute as the Russian, who has come in for criticism during the winter, collected Fabregas' pass and, with a hint of offside before Rodwell got his head to the ball, finished with composure.
Howard was cautioned for holding onto the ball in the aftermath of the goal and shortly afterwards Osman became the fifth Everton player to go into the book as a result of a trip on Walcott.
Things got worse for the visitors and six minutes after being pegged back they were forced to face up to the reality of another empty-handed return from North London as, criminally, Koscielny was left unmarked to head past Howard at a corner.
