Eden Hazard set up the decisive goal for Marcos Alonso as Chelsea came out on top in a frenetic London derby.
For 20 minutes Chelsea were so good it looked like it would be a rout, with goals from Pedro and Alvaro Morata their reward.
But Arsenal roared back to level through Henrikh Mkhitaryan and Alex Iwobi within five first-half minutes.
Sportsmail's Sami Mokbel rated the players on Saturday.
Chelsea (4-3-3)
Kepa Arrizabalaga - Solid enough, but should have done better Mkhitarayan’s strike which squirmed past his right hand. 6
Cesar Azpilicueta - Dependable as ever and notched an assist for Morata’s first-half goal to boot. 7
Antonio Rudiger - Fast becoming a crowd favourite. Another all-action defensive performance by the Dutchman. 7
David Luiz - Looked entirely comfortable at the back until Arsenal’s unlikely response of scoring twice in four minutes in the first-half. 6.5
Marcos Alonso - A match-winning contribution. Assisted Pedro’s opener before emerging as Chelsea’s hero with late strike. 8
N’Golo Kante - Playing in a more advanced role, but the Frenchman was just as dynamic in Chelsea's midfield 7.5
Jorginho - Over 100 touches of the ball. The summer signing from Napoli looks every inch a top tier Premier League footballer. 8.5
Ross Barkley - Encouraging display from the midfielder. Looks fit and invigorated. Heavily involved until his substitution. 7
Willian - Started brightly but faded as Arsenal hit back. Replaced by Hazard in the 61st minute. 6
Alvaro Morata - His well taken goal should do him the world of good. Still plenty more in the locker, though. 7
Pedro - Kept his cool to put Chelsea ahead by by sweeping in an Alonso cross on the counter. A regular threat for the Blues. 7
Subs: Kovacic 6 (Barkley 60); Hazard 7.5 (Willian 60); Giroud 6 (Morata 75)
Subs not used: Caballero, Moses, Giroud, Christensen, Zappacosta.
Maurizio Sarri - Two wins from two. The early signs are promising for Chelsea’s latest boss. 7.5
Arsenal (4-2-3-1)
Petr Cech - Produced some good saves to ensure hung in there with a punchers chance. 7
Hector Bellerin - Went walkabout for Chelsea’s opener. Thrilling in attack but questions remain over defensive work. 5.5
Shkodran Mustafi - Feeble defending for Morata’s goal. Hasn’t lived up to his £30m price tag. Booked. 5
Sokratis - Recovered from Chelsea’s early onslaught to put in a solid enough display. 6.5
Nacho Monreal - Has hardly trained but his energy in closing down Willian created Arsenal’s key first goal. 6.5
Matteo Guendouzi - Looked lost in early stages but showed promising signs as he grew into the game. His passing was efficient. 7
Granit Xhaka - Gave the ball away with his first touch. Booked. Hooked at half-time. Oh dear. 4
Henrikh Mkhitaryan - The instigator of Arsenal’s surprising come back. A goal and an assist means - at least on a personal level - a satisfying day’s work. 8
Mesut Ozil - A passenger yet again. Emery was bold in hooking the German - but 100 percent the right decision. 4.5
Alex Iwobi - A surprise selection but justified his manager’s faith with a decisive contribution. 7.5
Pierre-Emerick Aubameyang - Missed some glorious opportunities. Arsenal could have been out of sight had he been more clinical. 6
Subs: Torreira 6 (Xhaka 46); Ramsey 6 (Ozil 68); Lacazette 5.5 (Iwobi 75)
Unai Emery - Will be encouraged by his team’s comeback. But fact remains that it’s two defeats from two in the post-Wenger era. 6.5
Subs: Leno, Elneny, Welbeck, Lichsteiner
Referee - Martin Atkinson - 6.5
Att: 40, 491
MOM: Jorginho
Dihdirtuy
77
Our Coach also has a problem, Arsenal allowed so many goals bcoz the midfield of Xaka, so why does he want to continue with the same problem? Bought Lucas ad the other boy to sort out our problems in the midfield ,so why not start them both? Pliz sell Xaka ad Cech thy don't fit in ad suit the system of playing from behind plz plz plz
Africa7504509
45
Kante should be given time off in our next few games. I want Chelsea to try it out with Kovasic. Gorginho and Barkley at some point. Believe me the attack will be so straight forward and somewhat balanced in all.
DeGiro
44
this writer is a Chelsea supporter. how can you rate Jog higher than Iweobi? Iweobi's contribution and goal together was far more than joginho. or they are trying to hype this Joginho guy like they did on Morata.
emondorock
36
Dissapointing not even a point.Same old problem not scoring. Ozil needs bootcamp he was rubbish who ever decided to pay him 350 000 a week needs to go as well. Poor start and loosing to Chelsea not a happy gunner