The Gunners looked to take control of the derby after an energetic start in north London and Arsenal edged into a 10th-minute lead courtesy of Pierre-Emerick Aubameyang’s penalty.
For all Arsenal’s early dominance, the hosts were unable to extend their lead and England international Eric Dier equalised against the run of play with a close-range header in the 30th minute.
Tottenham edged into an unlikely lead when Harry Kane netted from the spot after Rob Holding was penalised for bringing down Son Heung-min in what looked like a soft penalty decision.
Emery made two significant changes at half-time as he brought on Alexandre Lacazette and Aaron Ramsey for Alex Iwobi and Henrikh Mkhitaryan.
The substitutes made a big difference to the north London derby after Ramsey provided assists for Aubameyang and Lacazette to turn the game on its head.
The France striker placed a finish past Lloris despite losing his footing before Lucas Torreira capped a thrilling 4-2 victory over Spurs with a clinical goal.
Arsenal shareholder and television personality Morgan, who was an outspoken critic of Arsene Wenger, took to Twitter to praise Emery for his shrewd tactical manoeuvres.
Morgan wrote on Twitter: “4-2. This Arsenal team FIGHTS.
Our best performance for years. Stunning turnaround, dazzling football – and such passion. Love what @UnaiEmery_ has done to our club. #afc”
The Good Morning Britain presenter was particularly pleased with the performance of Torreira, who arrived at Arsenal in a £26m deal from Sampdoria in the summer.
— Piers Morgan (@piersmorgan) December 2, 2018
Morgan praised Aubameyang after the Gabon international scored twice in the derby clash to become the first player to reach double figures in the Premier League this season.
He wrote: “Finally, we have a proper striker again. Brilliant player @Aubameyang7. #afc”
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