To add depth in the CAM role
Chelsea currently have Frank Lampard, Willian and Juan Mata to take the central attacking midfield role, and all are so different and individualistic that it gives Chelsea so many options in attack when starting a game. Lampard is a more textbook British midfielder who tries to get the job done even if it isn’t pretty, while working hard but lacking in technical ability. Willian is a box of tricks. Full of skill, flair and can bamboozle defenders with outrageous trickery while also having technical skills in abundance, though he is not always the hardest worker.
Juan Mata meanwhile is the team player, the type that every manager wishes for. He is fast, skillful, has an eye for goal and is a wonderful passer, though does not always get the job done and rarely covers his defensive duties. Guarin however is a mixture of them all, hardworking, skillful, technical and can drop back to a deep-lying role, and it is a player of his type who every team wants. Chelsea may have too many midfielders, though not any as versatile as the Colombian International.