A cursory glance at Monday night's match will reveal that after flirting with the 4-4-2/4-2-4 formation at the start of preseason, Antonio Conte opted to start the match with the 4-1-4-1/4-3-3 system seen in the final two preparatory matches. And it was working well until West Ham lucked into a goal; Conte then shifted gears into the more attacking two-forward system and was rewarded with the winner. Pre-season thus paid off two-fold, and Chelsea appear to have two solid tactical systems to choose from during matches, both of which at their core rely on effort, pressing, compactness in defense and width in attack.
At the top, we have punditry all-star Gary Neville and sidekick Jamie Carragher on Sky's Monday Night Football concentrating largely on analysis of individual players, especially Eden Hazard and, media darling, Diego Costa. Carragher also gives praise to Batshuayi's great run and header getting the better of a pretty good defender in Winston Reid to set up Costa's winner.
The MNF crew touched on the midfield, but Martin Lewis's analysis goes a bit deeper into the zonal press employed by the trio of Kanté, Matić, and Oscar — three "tactically disciplined midfielders", as Michael Cox of Zonal Marking puts it in his brief analysis. Martin's analysis is certainly well worth a click, and if you'll notice on the left side of his site, he has notes on all six of Conte's preseason matches as well.
I analysed Conte's first game at Chelsea, with a late win against West Ham: https://t.co/IAbDxhIFKM— Martin Lewis (@martinlewis94) August 16, 2016
Oscar was key in transition as well, both when combining with his fellow wide players on the right flank (Willian and Ivanović) and when switching the point of attack, such as shown in this GIF:
The long diagonals weren't really working on the day, but the right-sided trio was fun to watch and came up with several combinations that would've made the famous MaZaCar of 2012-13 jealous. There was a distinct difference between how the right flank and the left flank operated, especially in the first half when César Azpilicueta did not join the attack very often, leaving Hazard to rely on his considerable individual magic. Later on, the left-sided trio were quite adept at keeping possession, though as pointed out by Gary Neville, this slow and largely unimaginative passing perhaps wasn't exactly to Conte's liking.
The strategic asymmetry is further expounded upon by the venerable Spielverlagerung, who also point out that unlike in preseason, Chelsea's attacks were far less "patterned". Whether this is a one-game thing — as we saw from Italy at the Euros, Conte is a big fan of certain attacking patterns, like the quick second ball around the corner or over the top in behind the defense — or something more suited to our current group of players will reveal itself in due time.
Let's close out with a couple stats-based graphics. Here's @11tegen11 showing just how wing-focused Chelsea were in possession. Proper width is something we haven't seen in ages, and the continuing use of not just Hazard and Willian, but Moses and Pedro (and Cuadrado?) in such a system is something to look forward to after Monday's result.
Lastly, Michael Caley's expected goals chart shows that there's plenty of room for improvement in terms of quality chance creation. Solid stuff in defense however.