Liverpool saw their hopes of achieving a record Premier League points total extinguished at Arsenal as two errors resulted in a 2-1 loss for the champions.
The Reds needed at least a point to remain in with a chance of equalling Manchester City's 100-point haul from two seasons ago, and their hopes of reaching 102 were boosted by Sadio Mane's opener.
However, uncharacteristic gaffes from Virgil van Dijk and then goalkeeper Alisson saw the Gunners come from behind as they put Sunday's defeat to rivals Tottenham behind them.
Alexandre Lacazette equalised and Reiss Nelson scored his first Premier League goal to leave Liverpool on 93 points with just two games remaining.
There was an early warning regarding Emiliano Martinez's clearances when Roberto Firmino charged down one of his attempts and blocked the ball onto a post.
Ten minutes later, Martinez was harried again and Liverpool won the ball back from his kick, with Firmino releasing Andy Robertson to slide across for Mane, whose first-time finish gave the Reds a 20th-minute lead.
However, Arsenal quickly turned the game around following mistakes from Van Dijk and then Alisson.
First, Van Dijk, under pressure from Nelson, played a loose pass between Fabinho and Alisson, allowing Lacazette to capitalise for the equaliser.
Alisson was the next to sloppily give away possession, Lacazette again seizing upon the ball and squaring for Nelson to give the Gunners the lead prior to the interval.
Liverpool almost hit back early in the second period when Mohamed Salah, making his 150th appearance for the club, sat down David Luiz with a dummy before prodding towards goal only to see Martinez tip over the crossbar.
Jurgen Klopp called for Takumi Minamino from the bench and, after he dragged one shot wide, the Japan international felt he should have had a penalty when Kieran Tierney's pressure on him in the box went unpunished.
Salah then directed a weak header straight at Martinez, Mane fired a great opportunity wide and Trent Alexander-Arnold's deflected effort was saved as Liverpool saw their chance of becoming centurions pass them by.
What does it mean?
There was always a danger that Liverpool might fail to maintain their relentless pace once the season resumed, and this was the fourth time in seven games since the restart that they dropped points.
Their status as champions is, of course, already confirmed, but a record points haul is now beyond them. For Arsenal, this was an all-too-rare victory over a 'big six' club, which bodes well for the future and keeps them in the hunt for a top-six finish.
Lacazette not lacking
It is now three goals in four games for Lacazette, who has reached double figures in the Premier League in each of his three seasons in London.
His quick thinking saw him make the most of Liverpool's errors and, having looked like a spare part early in Mikel Arteta's reign, Lacazette is making himself a vital cog again.
Alisson all at sea
Van Dijk should cop the flak for the first Arsenal goal but, having just seen his team-mate make such a basic error, Alisson's blunder was even more unforgivable.
The arrival of those two in 2018 transformed Liverpool into Champions League winners, and then Premier League champions, but this was a night to forget.
Key Opta Facts
- Arsenal have beaten Liverpool for the first time in the Premier League since April 2015 (4-1), with this being the first time Klopp has suffered defeat against the Gunners in the competition (W5 D3 L1).
- Liverpool suffered their first Premier League defeat in a game they opened in the scoring in since April 2017 (1-2 v Crystal Palace), ending a run of 83 consecutive league games without losing after scoring the opening goal.
- This was Arsenal’s first Premier League win against the team starting the day top of the table since February 2016 (2-1 v Leicester), having lost each of their previous five such games.
- Lacazette has been directly involved in four goals in three Premier League appearances against Liverpool at Emirates Stadium (two goals and two assists).
- Nelson netted his first Premier League goal for Arsenal, becoming the fifth different player aged 20 or under to score for the Gunners in the competition this season.
- Mane has scored six goals against Arsenal in the Premier League; only against Crystal Palace (nine) does he have more in the competition.
Pierre-Emerick Aubameyang – who started on the bench as one of five changes – will be expected to return to the starting line-up for Arsenal's FA Cup semi-final against Manchester City on Saturday. Liverpool will hope to complete an unbeaten Premier League season at Anfield against Chelsea next Wednesday, when they will also finally get their hands on the trophy.