For us, he played as the central defender in a three at the back system. He did his fair share of front foot defending, especially in counterpressing situations but not as much as the R/LCBs. Instead, he was more important in defending counter attacks. His speed (I think he reached 35 km/h in some games) and strength is excellent for that and was a key enabler for the high line we play. As said, he lost a fair bit of muscle mass before his ascend to form and it made him more agile and improved his acceleration but he there were two or three occasions when he was taken by surprise by the strength of a really physical striker (Antonio, Boniface, Lukaku).
Last season, he was very basic in the build up. His biggest strength is transitioning after winning the ball. Where other CBs pass it backwards to the keeper, Tah has excellent vision and often finds a surprising forward pass that sets the team up for a counter attack or possession phase, sometimes he even combines it with a bit of tidy footwork. This season, he has also improved his passing massively. One of his long balls to Frimpong lead to the red card against Neuer. He's decent at those passes now but still nowhere near Hummels, Boateng, Bonucci, van Dijk and those kind of CBs.
His heading is very good. Alonso occasionally likes to defend deep in his own half and we have to deal with lots of crosses in those phases. But for a very long time, Tah was one of those CBs that left you wondering how somebody so good at defensive headers could be so terrible at offensive headers since he went whole seasons without scoring one. That improved as well under Alonso and Tah was one of our biggest threats from set pieces, often being involved in our trademark late goals in some capacity.
All that being said, I still can't say he'll be a huge success wherever he goes because I'm not sure how he deals with more negative stress than he had in the last two years with us. As said, in the past he was extremely error prone. It seems he really has developed in that respect particularly but we all know bad habits die slowly. Really hope he'll hit the ground running wherever he goes, though, since he comes across as a very likeable guy. Was very popular among the young players and overall an important figure in the dressing room, speaking multiple languages and all that.
