Arsenal and Chelsea played out a pulsating 2-2 draw on Wednesday night, with both teams throwing caution to the wind in an attempt to win the game.
Jack Wilshere put the Gunners in front just after the hour mark, before the visitors turned it around with an Eden Hazard penalty and Marcos Alonso's neat finish to seemingly take a crucial three points back to Stamford Bridge.
But Hector Bellerin stepped up two minutes from time to fire in from close range and rescue a point for Arsene Wenger's men, in one of the games of the season so far.
Here's a few things we learned from an all-time great London derby:
4. Jack Wilshere Is Back to His Best
With every passing game, Jack Wilshere looks to be approaching a level near his very best, where he is simply unplayable and can unlock any defence in world football. Despite having just six months left on his contract at the Emirates, it now seems unthinkable that Arsene Wenger could contemplate letting the 26-year-old leave.
The Englishman completed his sixth successive 90 minutes in the Premier League on Wednesday, and scored his first goal since the final day of the 2014/15 season, beating Thibaut Courtois with a terrific strike.
With a World Cup in the summer, every incentive is there for the oft-injured playmaker to kick on and make sure he is on the plane to Russia in June.
3. Thibaut Courtois Is Crucial to Chelsea's Hopes This Season
Despite Petr Cech putting in a good performance at the other end of the pitch, it is fair to say Chelsea backed the right horse when they phased out the club legend three years ago in favour of Thibaut Courtois.
The Belgian was outstanding on Wednesday night, making several outstanding saves to keep Arsenal at bay in the first half, including a remarkable fingertip stop which ricocheted off both posts to deny Alexis Sanchez.
Courtois has been linked with Real Madrid in recent weeks, and after tonight's performance, the Chelsea board must do everything in their power to keep him in west London for the foreseeable future.
2. Chelsea Need to Sign a Striker in January
Alvaro Morata was nowhere near his best at the Emirates, going through on goal with Petr Cech to beat on several occasions, only to miss every time. With one of the last actions of the match, the Spaniard was one-on-one in injury time, but tamely hit the ball straight at the Arsenal goalkeeper.
Antonio Conte could sense his number nine was having a bad game, yet couldn't substitute him, with the Italian lacking any real trust in the club's only other first-team striker, Michy Batshuayi.
The Chelsea hierarchy must realise the need for reinforcements up top and dip into the market to give their £60m summer signing some much-needed competition.
1. Arsenal Urgently Need Defensive Reinforcements
With injuries to Laurent Koscielny and Sead Kolasinac at West Brom depleting Arsenal's defensive options, Arsene Wenger had to opt for an untested back three with youngsters Rob Holding and Calum Chambers either side of the inconsistent Shkodran Mustafi.
Were it not for the aforementioned wastefulness of Alvaro Morata, the visitors would have been out of sight long before Hector Bellerin's dramatic equaliser. With Koscielny now 32 and Per Mertesacker retiring at season's end, Arsenal have to start preparing for life after the duo.
Gunners fans were bemused by today's announcement that a deal for 20-year-old Greek defender Kontantinos Mavropanos is close, with the Emirates faithful longing for an accomplished, big-name signing at the heart of the back four. Arsene Wenger must enter the transfer market to address their obvious frailities.