Tottenham playing a classic 4312 with attacking fullbacks and doing it properly. Makes me a little nostalgic to see it done well!
I think Chelsea are really lacking in offensive firepower right now and a balance between ball to feet players and runners.
Hazard and Willian both like the ball to their feet and are primarily creators, while only Pedro offers a threat in behind the defence.
They lack a proper striker and an offensive midfielder to contribute in the final third. Mertens worked as a false 9 with Sarri as he has always been a player who attacks space well and carries a serious goal threat.
Hazard drops off to dribble and pass and move, so just doesn't possess the characteristics to play there. Kovacic isn't a final third player as he is better playing deeper spraying passes and using his press resistance to help with deep buildup. He is no Hamsik that combines with the attackers, and carries a serious goal threat.
Just those two players will make a significant difference to their offensive firepower.
Newcastle 2 - 1 Man City
Manure 0 - 2 Burnley until '87
Bournemouth 3 - 0 Chelsea
Liverpool 1 - 1 Leicester
Tottenham 0 -1 Watford
Fiorentina 7 - 1 Roma
Atalanta 3 - 0 Juventus
Milan 2 - 0 Napoli