Slavia once again approached the game with very high and aggressive pressing, where they wanted to play on the front foot, push up and press Chelsea into tight spaces.
Slavia’s pressing was difficult to break through since they played with a 3-4-1-2, matching Chelsea all the way through the middle of the pitch (2v2, 3v3, 3v3), while their wing-backs would push up on the side of the ball to cover Chelsea’s fullback, leaving the far side fullback in space while Slavia’s far side wing-back held a deeper position to provide support in midfield.
Slavia’s players would switch positions throughout the half too. Sevcik started in the front, before moving over to the right; Zmrhal started on the left before moving up to play in the front two; and Boril went from the right to the left.
Although Slavia’s pressing was matching Chelsea’s numbers, and it was consistent and aggressive, it did leave them vulnerable at the back to quick attacks when Chelsea played a pass through their midfielders, especially given the qualities of Chelsea’s front three. Slavia would compensate for this by making fouls in midfield (the defenders would always try to get ahead of the Chelsea attackers receiving the ball to intercept the ball), which would prevent Chelsea advancing into the final third on a few occasions, but it would also allow Chelsea to start attacks from midfield and not have to break through the same intensity of pressure again.
When playing from midfield and entering the final third, Chelsea were clinical early on in the game and quickly built a lead though combinations and recovering the ball higher up against a stretched team. Kanté helped Chelsea a lot compared to the first game (when he didn’t start), as Chelsea could now press high up on the right and recover second balls in midfield before quickly launching attacks.
Despite going behind, Slavia continued to press and attack in numbers, where they would go on to cause problems from a similar set piece as in the first leg, before pulling a goal back from a corner. Chelsea were again quick to respond to this and recovered their lead straight from the kickoff to go into the break with a 4-1 lead in the match, 5-1 on aggregate.
For the second half, Slavia switched to a 4-4-1-1. They continued to press high, but with one less forward to keep a spare man at the back (4v3 rather than 3v3). This allowed Chelsea to keep the ball in their half and find a spare man, or keep going back to Kepa to restart attacks, but had much more difficulty moving the ball forward and moving into the final third.
Without being as exposed at the back, Slavia could recover the ball and continue to attack in numbers down the wings, which would present them with the two goals early on in the second half and another chance inside the box, which they didn’t take.
For the remained of the half Slavia continued putting the ball into the box, winning set pieces, and pressing high with numbers and intensity always on the ball. Chelsea became split between the backline and frontline, where the back four were often narrow and in defensive positions when Chelsea had the ball — unable to get out or behind the press — and the frontline became too isolated from the midfielders when the ball was played direct to Giroud. Without being able to move forward with the ball, Chelsea would instead defend deep for the final stage of the match, doing well in clearing balls in the box to prevent chances and see the game out.
Chelsea vs Slavia Prague Running xG pic.twitter.com/yobpCgeYbX— Crab Stats Graphics (@CrabStats) April 18, 2019
Chelsea were clinical in taking advantage of the moments when they broke through Slavia’s high and aggressive pressing in the first half, building a significant lead by halftime. In the second half, Chelsea had more problems against the adjusted pressing and conceded two early goals from similar positions. Slavia had one more good chance early on in the second half which would have made a big difference in the game, and continued pressing high, but Chelsea had the comfort of the two goal lead — despite problems with the ball — to hold onto result and see the game.