If he did not know already, then Mauricio Pochettino would have found out first hand just how much work he has to do as Chelsea head coach on Sunday afternoon.
The Blues came into the game on the back of a 1-1 draw with Liverpool where there were many positives to take for Pochettino. Apart from the opening stages of the first-half, Chelsea more or less dominated the Reds at Stamford Bridge and were unfortunate not to walk away with all three points on the opening weekend of the season.
So with a week to prepare his new squad for the trip to the London Stadium to face West Ham United, Pochettino was feeling pretty positive about his start to life at the club. That would have only been added to by the double arrival of Moises Caicedo for £115million and then the £58m signing of Romeo Lavia a few days later.
Both midfielders were registered in time to make their debuts for the Blues on Sunday afternoon in East London. However, it was only Caicedo who made the squad.
The Ecuador international, though, was deemed not quite ready to start the match. It wasn't until the hour-mark until Pochettino turned to his record signing. It was eight minutes after Michail Antonio had restored the Hammers' lead in front of a buzzing London Stadium.
Caicedo came on and slotted into the No.6 role, with Enzo Fernandez and Conor Gallagher playing as the No.8s either side of him essentially. His first touch as a Chelsea player was a slide tackle, but an unsuccessful one where, despite making contact with the ball, he was unable to win back possession. That kind of set up what turned out to be a massively eventful and disappointing debut for Caicedo.
Every word from Mauricio Pochettino on West Ham vs Chelsea, Caicedo debut and Mudryk form
Playing at
Read on football.london