Chelsea's pre-season tour of the United States ended in a 4-0 defeat to Arsenal in Orlando at the Camping World Stadium.
Thomas Tuchel's side improved in the second half after changing their shape, but the damage was done as Mikel Arteta's side took the London bragging rights back to the English capital.
Gabriel Jesus put Arsenal into the lead after 15 minutes in Orlando, punishing a Chelsea defensive error and coolly putting it into the back of the net. Martin Odegaard deservedly double the lead with a fine finish past Mendy in the 36th minute.
Advert
Bukayo Saka added a third 21 minutes into the second half, despite replays showing he was offside, after tapping in from yards out following a double save by Edouard Mendy. Albert Sambi Lokonga added a fourth in stoppage time.
Despite it being a pre-season friendly, there was no friendliness early on. Raheem Sterling left one on former teammate Gabriel Jesus early on, while Conor Gallagher made a couple of strong fouls in the opening minutes.
Arsenal had the first big chance of the game inside six minutes. A Chelsea corner fell into the feet of the Gunners' attack as Gabriel Martinelli played in Bukayo Saka one-on-one with Edouard Mendy, but the Blues made a comfortable save to keep the scores level.
Advert
But Arsenal went ahead after 15 minutes. Trevoh Chalobah's misplaced pass was punished as Jesus, found in open space, dinked the ball over Mendy to put the 'hosts' into an early lead.
Chelsea looked miles off the pace in the first half and they were punished nine minutes before the break. Martin Odegaard double Mikel Arteta's side lead after taking Martinelli's ball in his stride to fire past Mendy from close range.
Chalobah was forced off in the 44th minute with a knock as Malang Sarr replaced him.
Advert
Mason Mount had Chelsea's first real chance of the game in stoppage time. Raheem Sterling pulled it back to the 23-year-old, but his effort cannoned back off of the post.
Tuchel saw enough at the interval, reverting back to a back-three, bringing on Cesar Azpilicueta, Marcos Alonso, Mateo Kovacic and Christian Pulisic who replaced Emerson Palmieri, Conor Gallagher, Raheem Sterling and Timo Werner.
After switching back to their preferred system and with the introduction of Kovacic, Chelsea looked much more comfortable on the ball in the second half.
Advert
Kai Havertz and Mount's evenings were completed after 64 minutes as Tuchel refreshed the attack with Hakim Ziyech and Michy Batshuayi.
Saka added a third to kill the game in Florida. Mendy made two big saves to deny Martinelli and Granit Xhaka, but Saka was there to tap home from close range in the 66th minute.
Kalidou Koulibaly made his first appearance for the Blues since joining, replacing Thiago Silva with 17 minutes to play. Ethan Ampadu and Callum Hudson-Odoi were also given run-outs, replacing Reece James and Jorginho.
The 31-year-old made a superb block to deny Nicolas Pepe from scoring a certain fourth to avoid further misery being piled on the Blues.
Advert
Chelsea couldn't find the net to grab a consolation goal as the whistle blew in Florida to mark the end of their US tour.
But Arsenal found another in stoppage time to run riot in America as Albert Sambi Lokonga added a fourth to inflict more damage on Tuchel's side.
There is plenty of work still to do for Tuchel's men with less than two weeks to go until their Premier League opener against Everton.
Matthew Debono