The Blues have wrapped up the signing of Kurt Zouma, who has been linked to the club fairly heavily for over a year now. The 19-year old has signed a five and a half year deal with the Blues, and will remain in Ligue 1 for the remainder of the season on loan.
Zouma will likely be in the mix for a first team place when he arrives, though he'll likely have competition from Kenneth Omeruo and Tomas Kalas. While this doesn't necessarily mean that either of John Terry or David Luiz will be departing, it certainly makes it easier for the club to cope if they do.
St. Etienne will likely have a whole bunch of new fans now, as I'm sure many have just found themselves a reason to pay attention to Ligue 1. Zouma is expected to start for St. Etienne on Saturday when they face Valenciennes.