Chelsea beat Arsenal 2-1 in a pre-season friendly at the Emirates on Sunday, although they were fortunate to do so with the Gunners quite clearly robbed of a late equaliser.
The London rivals met in the first of a three-game series including Tottenham in which each team will play each other once to prepare for the start of the new Premier League campaign.
Kai Havertz gave Chelsea the perfect start as he smashed them into the lead on 26 minutes after being set up by Timo Werner.
It was the Germans’ first appearances for their club side since the Champions League final in May and winning goalscorer Havertz picked up where he left off.
Emile Smith Rowe and Hakim Ziyech both hit the post for their respective sides, but made no difference to the 1-0 scoreline at half-time.
Ziyech failed to convert another great chance early in the second half as he knocked the ball over Bernd Leno, but took too long trying to evade Pablo Mari and could not find the finish.
Arsenal levelled in the 69th minute as Granit Xhaka got on the end of a Nicolas Pepe corner and headed past Kepa Arrizabalaga.
Just three minutes later though, the Gunners gifted Chelsea their lead back.
Hector Bellerin misplaced a backpass and put Tammy Abraham in on goal.
He finished coolly to put the Blues 2-1 up.
With nine minutes to go, Arsenal appeared to have equalised once more, but no goal was given.
Nicolas Pepe drew Kepa out of goal and set up Joe Willock for a shot which rattled the crossbar and bounced downwards.
At first glance it appeared to have crossed the line and replays confirmed this impression.
However, with no goal-line technology or VAR in use for the friendly, the officials had to make the call alone.
The score remained 2-1 and Chelsea saw out the win.