Bolton 2-2 Arsenal
Bolton Wanderers delivered a devastating blow to Arsenal's title ambitions with a stunning comeback at The Reebok Stadium.
Arsene Wenger's side looked on course to return to the Premiership summit as they cruised into a two-goal lead early in the second half.
Sylvain Wiltord and Robert Pires put Arsenal in command - but relegation-threatened Bolton did Manchester United a massive favour in stirring fashion.
Youri Djorkaeff put Bolton back in contention before Martin Keown's own goal gave Sam Allardyce's men an unlikely point.
Bolton's Florent Laville was sent off in an agonising six minutes of injury time before Arsenal were left desperate and despondent at the final whistle.
46 mins: Wiltord puts Arsenal ahead ahead.
55 mins: Pires increases Arsenal's lead.
76 mins: Djokrkaeff puts Bolton back in contention.
83 mins: Keown's own goal puts Bolton level.
92 mins: Bolton's Laville is sent off.
It leaves Arsenal two points behind United having played the same amount of games, giving their title rivals a massive incentive to win at Spurs on Sunday.
Arsenal kept Keown on the bench - with Sol Campbell partnering Pascal Cygan in his final game of the season before suspension.
And they were kept on their toes as Bolton belied their lowly league position with a spirited first half showing.
Henrik Pedersen was narrowly off target with a left-footed drive which had David Seaman scrambling across his goal.
And Jay-Jay Okocha's free-kick looked destined for the bottom corner until it took a vital deflection.
Arsenal barely posed a threat in a colourless opening 45 minutes - but they burst into life in spectacular fashion after the break.
It took less than two minutes for Arsenal to break the deadlock, and once again Thierry Henry was the inspiration.
He raced away from Bruno N'Gotty and slipped a perfect pass to Wiltord, who completed the formalities from virtually on the goal-line.
And Arsenal struck another blow in the 55th minute with another exquisite finish from Pires.
Henry set up his fellow countryman, who delivered a measured finish past Jussi Jaaskelainen from 20 yards.
Wenger was left despondent
Arsenal's joy was tempered a double injury blow, as Freddie Ljungberg limped off with an ankle injury following a late tackle from Okocha.
And then Cygan increased Wenger's defensive worried when he appeared to pull up with a calf strain and was replaced instantly by Keown.
Bolton were handed a lifeline with 14 minutes left when slack Arsenal marking gave Per Frandsen an opening on the edge of the area.
He struck the post, and Djorkaeff was on hand to score.
Arsenal were suddenly on the back foot, and Seaman was forced to save from Pedersen as Bolton suddenly found fresh hope.
Bolton were incredibly level with seven minutes left when Djorkaeff's free-kick glanced off Keown's head and beat Seaman.
As six minutes of injury time were signalled, Laville was sent off for his second bookable offence, a foul on Ashley Cole.
Bolton: Jaaskelainen, N'Gotty, Bergsson, Laville,
Mendy (Andre 71), Campo (Nolan 71), Frandsen, Okocha, Gardner, Djorkaeff, Pedersen (Salva 83).
Subs not used: Poole, Charlton.
Sent off: Laville (90).
Booked: Laville, Campo.
Arsenal: Seaman, Lauren (van Bronckhorst 72), Cygan (Keown 67), Campbell, Cole, Ljungberg (Luzhny 58), Parlour, Silva, Pires, Henry, Wiltord.
Subs not used: Bergkamp, Taylor.
Booked: Henry, Parlour.
Referee: A D'Urso (Essex).