Arsenal closed to within a point of Tottenham and maintained their arch-rivals' miserable record at Emirates Stadium with a comfortable north London derby victory.
The pressure was on Arsene Wenger and the Gunners as they trailed Spurs in the Premier League table - but they responded in style and were superior in all areas of the pitch to win with plenty to spare.
Shkodran Mustafi headed a free-kick powerfully past Spurs keeper Hugo Lloris in the 36th minute after referee Mike Dean had contentiously penalised Davinson Sanchez for a challenge on Alexis Sanchez. The German defender also looked to have been offside.
Spurs manager Mauricio Pochettino said: "I do not need to say anything. It was obvious for everyone here and watching at home. It is not easy to accept because we lost the game but we have to move on and keep going.
"The free-kick for the first goal and the first goal was obvious offside, maybe the second was too. When you play against a team in the top six, the big details are up to you. Sometimes things go against you but that is football.
Wenger added: "The free-kick was a free-kick for me. We have had bad luck away from home - I'll leave that to the specialists."
Arsenal's domination was underlined five minutes later when Sanchez finished emphatically at the near post, effectively securing the Gunners' first league win over Spurs since 2014.
Tottenham - who have only once in 12 league visits to the Emirates - suffered with Harry Kane, looking well short of match fitness after missing England's friendlies against Germany and Brazil with a hamstring injury, rarely threatening, although Arsenal keeper Petr Cech saved athletically from Eric Dier's late header.
Wenger has mysteriously often decided against using Ozil, Lacazette and Sanchez as a potent three-pronged attack this season.
This was only the third time he has used the three players together and the combination's potential and threat was obvious as Spurs were outplayed for most of this north London derby.
It also begged the question why it was not used - with £52m Lacazette the most obvious victim of Wenger's selection policy - in the 4-0 thrashing at Liverpool and the 3-1 loss at Manchester City earlier this season.
The France striker is already a popular figure among Arsenal fans, as proved by the fierce jeering when he was replace by Francis Coquelin with 17 minutes left, while Sanchez and Ozil have long been providing the attacking class for the Gunners.
Sanchez can be high maintenance and Ozil mercurial, but the three were at Spurs' throats from the start, providing fluidity and danger the visitors found almost impossible to control.
Lacazette and Sanchez were central figures in the crucial second goal, lashed into the roof of the net from an angle by the Chile international.
And Ozil, the languid and elegant German, was full of energy and creation.
This outcome will surely have crystallised Wenger's thoughts on the matter - Arsenal are a much more complete and threatening proposition with the three together than without them.
Tottenham rightly received all the plaudits for a magnificent demolition of holders Real Madrid in the Champions League at Wembley - but a pattern is emerging that must be of concern to manager Pochettino.
Pochettino's side came up short in a hard-fought match at Manchester United last month - and were miles off the expected standard as they slumped to a loss they can have few complaints about at their arch-rivals on Saturday.
Spurs' last win away at a fellow member of what might be termed the Premier League's 'big six' came with a 2-1 victory at Manchester City on 14 February 2016.
The Emirates has been a grim place for Tottenham to come to, with only one win in 12 visits with seven defeats - a statistic they never looked like changing here.
There was little doubt captain and main marksman Kane, who wore a large strapping on his right leg after missing England's friendlies against Germany and Brazil with a hamstring injury, was short of match fitness and Alli made no impact.
Pochettino's main worry will surely be that the drive, intensity and pressing he regards as a hallmark of the Spurs style all belonged to Arsenal on this occasion.
Yes, Tottenham can complain they were harshly dealt with for the first goal - but they were very much second best and this is something Pochettino will have to change if they are to make that elusive leap from runners-up to Premier League champions.
Arsenal 2-0 Tottenham: Wenger 'very proud' of Gunners performance The appointment of Mike Dean as referee for this north London derby created much debate among Arsenal supporters, who feel they have been on the rough end of decisions from the official in the past.
And some of Dean's early adjudications brought howls of outrage from Gunners fans - but in the end it was Spurs who were left complaining after a contentious decision led to the opening goal.
Dean punished Sanchez for what looked like a legitimate challenge, the resulting free-kick being headed past Lloris by Mustafi.
Arsenal boss Wenger was furious about the standard of officiating after the 3-1 loss at Manchester City on 6 November, saying after a third goal that replays showed was offside: "I feel referees don't work enough. The level drops every season at the moment and overall it's unacceptable."
On this day, however, Pochettino was the manager with cause for complaint.