Arsenal blew the Premier League title race wide open as Gabriel Martinelli punished a howler from Liverpool keeper Alisson Becker to inspire a crucial 3-1 win over the leaders on Sunday.

Martinelli fired home after Alisson completely missed his clearance in the second half to the delight of the Arsenal fans packed into the raucous Emirates Stadium.

Mikel Arteta's side had taken an early lead through Bukayo Saka before Gabriel Magalhaes's bizarre own goal gifted Liverpool an equaliser late in the first half.

Leandro Trossard bagged Arsenal's third in stoppage-time to clinch the points after Liverpool defender Ibrahima Konate was sent off in the closing stages.

Arsenal's vital victory moved them into second, two points behind Liverpool after 23 games each.

It was Liverpool's first domestic defeat in all competitions since September, when they lost just across north London at Tottenham in the Premier League.

Liverpool's devastating defeat was also a boost to champions Manchester City, who travel to Brentford on Monday.

City are five points adrift of Liverpool but have two games in hand and will go top if they win both.

Liverpool won at the Emirates just a month ago, beating Arsenal 2-0 in the FA Cup third round in part due to a series of key misses by the Gunners.

The sides also drew 1-1 in the Premier League at Anfield just before Christmas after Arsenal blew an early lead.

Arsenal, who would have been eight points behind the leaders if they had lost, finally got one over Liverpool as they inflicted a first defeat since Klopp announced his long goodbye on January 26.

Chasing a first title since 2004 after capitulating late in the race with City last term, Arsenal have issued a significant statement of intent.

Without Gabriel Jesus, after the often-injured Brazil striker suffered another knee problem in training this week, Arsenal at last showed the cutting edge required of champions.

Saka sparked pandemonium in the stands when the Arsenal winger struck in the 14th minute.

Martin Odegaard's pass to Kai Havertz exposed a gaping hole in the centre of Liverpool's defence and when the German's tentative shot was saved by Allison Becker, the rebound fell perfectly for Saka to fire home from 10 yards.

Arteta jubilation 

Arsenal were well on top at that stage as Liverpool laboured to establish any rhythm in the final third.

Yet Klopp's men equalised in first half stoppage-time thanks to a farcical goal gift-wrapped by the Arsenal defence.

Instead of clearing, William Saliba tried to hold off Luis Diaz as the Arsenal centre-back aimed to let the ball run through to keeper David Raya.

But Diaz tenaciously wrestled his way past Saliba and poked the ball into the six-yard box, where it hit Gabriel on the arm before rolling into the net.

Liverpool hadn't mustered a shot on target but they were still level.

The Reds nearly added to Arteta's angst early in the second half when Alexis Mac Allister fizzed a long-range drive narrowly wide. Then Curtis Jones' curled just past the far post.

After Arsenal's earlier present for Liverpool's equaliser, Klopp's men returned the favour in the 67th minute.

Alisson sprinted out of his area to deal with a long pass towards Martinelli and missed.

Virgil van Dijk also failed to clear, allowing Martinelli to fire into the empty net as Klopp stood stunned on the touchline.

Mac Allister was inches away from a spectacular equaliser when he volleyed wide from the edge of the area.

Konate was dismissed in the 88th minute for a second booking after catching Havertz.

Trossard smashed a low shot through Alisson's legs via a deflection off Van Dijk in stoppage-time, triggering a jubilant run down the touchline from Arteta as Arsenal dreamed of title glory.