We had gone behind early at the Emirates when Pierre-Emerick Aubameyang was left unmarked to head in at a corner, and an underwhelming start triggered Frank Lampard to make a change of personnel and formation on the half-hour, bringing Jorginho on for Emerson and reverting to a back four.

It worked, with Chelsea the better side leading up to half-time and then after it, too. Still, we had to find a way to goal. Clear chances proved hard to come by until seven minutes remained, when a Mason Mount free-kick was missed by all and sundry in the six-yard box, giving Jorginho an open goal from a yard out.

Arsenal, with just one league win to their name in two-and-a-half months, were there for the taking, and with three minutes left Abraham finished coolly at the end of a free-flowing counter-attack to seal another precious victory in a London derby.

It is our first league win this season having trailed, and we end the decade with the enjoyment of victories away to Tottenham and Arsenal in the same season for the first time since 2012.

Lampard selected a similar shape and team to the one which excelled a few miles down the road last Sunday, although it wouldn’t be long before the boss changed things. Mateo Kovacic returned from suspension at Jorginho’s expense, while Emerson was at left wing-back in Marcos Alonso’s continued absence through injury. Nineteen-year-old Tariq Lamptey was named on the bench for the first time in a Premier League game, and would later make an impressive debut.

In his first home game in charge, Mikel Arteta brought Calum Chambers and Matteo Guendouzi in with the Gunners seeking a first home win since early October.

It was a familiar face who threatened early on, David Luiz scissor-kicking wide from a Mesut Ozil corner. The defender then curled a set-piece into Kepa’s grateful arms from much further out.

Arsenal’s high press had disrupted our rhythm in the opening stages, but when we did attack with menace on 10 minutes we came close to breaking the deadlock. Willian was too quick for Matteo Guendouzi, who dragged him down on the edge of the box and was booked. Willian took the free-kick short to Mount, whose well-struck effort was held by Bernd Leno at the second attempt.

The save proved even more crucial as Arsenal took the lead a couple of minutes later. Chambers won the first header from another Ozil corner, and Aubameyang stole in front of Emerson to nod past Kepa from five yards out.

It needed a superb interception from N’Golo Kante to take the ball off the toes of his compatriot Alexandre Lacazette, who looked set to double the Gunners’ lead after the speedy Reiss Nelson had picked out Aubameyang.

Midway through the half, Chambers had to be replaced by Shkodran Mustafi after falling awkwardly.

As our frustration grew at not being able to implement our gameplan, Mount and Kante were booked in the space of 60 seconds for cynical fouls in midfield.

Lampard had seen enough and acted decisively, bringing Jorginho on for Emerson and switching to a back four, with Azpilicueta on the left and Fikayo Tomori the right.

It was Tomori who instigated a rare Chelsea attack down that flank, ending in a VAR check for a possible foul on Tammy Abraham (not given) and a Chelsea corner, flicked on by Azpilicueta but missed by the stretching Kurt Zouma at the far post.

Aubameyang fired into the side-netting with half-time approaching, but otherwise it had been a much brighter 10 minutes or so since Jorginho’s introduction – something to build on after the interval.

We did just that when play restarted, maintaining the momentum built up prior to the break. Kante volleyed wide from 20 yards and both full-backs found space in dangerous areas. More encouraging were the far greater number of tackles and duels won by those in blue.

Shortly before the hour, Lamptey came on for his Chelsea debut, replacing Tomori at right-back. It is a position he has often occupied for our youth teams.

His first involvement was to make a crucial interception with his chest, and he then superbly slipped in Abraham whose shot was blocked by the stretching David Luiz. Azpilicueta headed Willian’s follow-up cross over.

Callum Hudson-Odoi for Kovacic was our final sub with 20 minutes left. Mount dropped back into midfield.

A slick move involving Hudson-Odoi, Abraham, Willian and Mount almost set up a tap-in for Tammy, who headed straight at Leno from the resulting corner. It was a good chance.

Arsenal hadn't threatened much in the second half, but when Kante was dispossessed inside the box, sub Joe Willock thumped a whisker wide.

There was no let-up in intensity as the game entered its final 10 minutes and the yellow-card count approached double figures. Increasingly 10 red shirts were stationed behind the ball, with Arsenal inviting us to break them down if we could.

And that we did with seven minutes left! It was Jorginho who was fouled right in front of the Chelsea fans, and it was he who tapped in the resulting free-kick from Mount after Leno had come out and punched at thin air.

Having exposed Arsenal’s fragility once, and with the Emirates getting edgier, we sensationally took the lead with three minutes left. It stemmed from an Arsenal attack, as we won the ball back and broke at speed through Abraham. He slipped the ball wide right to Willian, whose first touch took him away from goal but his next pass was brilliant, cut back to Abraham who spun Mustafi and fired between Leno’s legs.

In seven minutes of stoppage time, Abraham shot over after winning the ball back on halfway, and down the other end Lucas Torreira volleyed past Kepa’s right post from 16 yards. It was the only scare as the Blues held on relatively comfortably, sparking more fantastic scenes between management, players and fans at the final whistle.

Happy New Year!

Chelsea (3-4-3): Kepa; Rudiger, Zouma, Tomori (Lamptey 59); Azpilicueta (c), Kante, Kovacic (Hudson-Odoi 70), Emerson (Jorginho 34); Willian, Abraham, Mount.Unused subs Caballero, Christensen, Barkley, Batshuayi.Scorers Jorginho 83, Abraham 87Booked Mount 30, Kante 30, Rudiger 33, Jorginho 55

Arsenal (4-4-2): Leno; Maitland-Niles, Chambers (Mustafi 23), David Luiz, Saka; Torreira, Guendouzi; Nelson (Pepe 86), Ozil (Willock 76), Aubameyang (c); Lacazette.Unused subs Martinez, Mavropanos, John-Jules, Smith Rowe.Scorer Aubameyang 13Booked Guendouzi 10, David Luiz 47, Torreira 73, Lacazette 77, Maitland-Niles 90+1

Referee Craig PawsonCrowd 60,309