/cdn.vox-cdn.com/uploads/chorus_image/image/65979587/2019_12_27_14.46.10.0.jpg)
First half
Chelsea had problems breaking Southampton down, both to stretch and get behind from from deep, as well as creating in the final third.
Southampton pressed high in numbers to the sides, especially when Chelsea’s wing-backs were deep to collect the ball from the central defenders. The front two would shift to the side of the ball and cover the passes back inside, forcing passes into pressure ahead of the ball. However, when the ball was lost, Chelsea were quick to recover the loose ball during the early stages of the game.
Southampton’s wide midfielders would drop deep to provide support to their fullbacks to cover the runs of Chelsea’s wing-backs, or to tuck inside and cover Willian or Hudson-Odoi when the fullbacks were quick to close down Chelsea’s wing-backs on the ball.
Chelsea had a difficult time progressing forward quickly from midfield to break Southampton’s lines or find the same overloads on the wings for long diagonals as they had against Tottenham (wing-backs high early). Many of Chelsea’s attacks would form by pushing Southampton back, where they could defend their box with organisation and numbers — wingers deep, central midfielders shifting quickly, one or both strikers dropping back deep.
After not being able to break Southampton down in the final third and continuing to have problems breaking through their lines in midfield, Chelsea faced an even greater problem by losing the ball in midfield — Emerson passes to Hudson-Odoi under pressure and overlaps, Armstrong leaves Emerson and doubles up on Hudson-Odoi to win ball — and conceding a goal from a quick counter attack.
Following the goal, Chelsea once again had a lot of possession in the final third, but continued to have difficulty breaking down Southampton’s deep block as well as trying to force chances and play the ball too quickly leading to them losing the ball often and becoming more and more frustrated.
Second half
Chelsea started the second half with Mount replacing Zouma and switching to a 4-2-3-1. With this change they replaced wing-backs (not having an impact on the game) with the extra creative player in the middle and this made a big impact on the game. They could now play to feet and use fast combinations between lines to advance through Southampton’s defensive block and create chances in the final third.
Southampton continued to pose a threat through counters, with Redmond really starting to show his qualities during their attacks. His speed both with and without the ball found him going into spaces and past players, while his capacity to make quick actions with few touches made him difficult to control. He both created chances and had a good chance of his own saved, before he got onto the end of a ball inside the box to poke it past Kepa and provide Southampton with a two goal lead.
Chelsea continued to push for the goal as they had during the start of the half, but Southampton’s aggression from midfielders and defending of their box continued to remain strong and prevented Chelsea from getting back into the game.
:no_upscale()/cdn.vox-cdn.com/uploads/chorus_asset/file/19558422/Screen_Shot_2019_12_28_at_03.46.13.png)
Conclusion
Southampton’s covering of Chelsea’s wing-backs high up and workrate from their wingers to drop back gave Chelsea a lot of problems with the ball during the first half. The wing-backs dropping for the ball and forward passes into pressure would also provide Southampton with opportunities to recover the ball high, counter, and take the lead. Chelsea’s change to 4-2-3-1 at half time help them break through Southampton’s lines in midfield and create opportunities in the final third, but Southampton’s threat with the ball through Redmond was a constant problem for Chelsea defensively, and he would go on to create chances and score to extend Southampton’s lead and take the three points.