Xabi Alonso has played under both Pep Guardiola and Jose Mourinho, and believes the rival pair are very similar in their approach to the game.
Guardiola and Mourinho are set to meet for the 17th time in their managerial careers on Saturday, but it will be the first time in English football.
Alonso played for Guardiola at Bayern Munich and Mourinho at Real Madrid, and he has lifted the lid on how they work behind the scenes.
'It is a very big game in England,' he told reporters in Germany.