The January transfer window has never been the ideal time to do business in football.
Clubs put ridiculous prices on their best players and half of them are cup-tied for all of the major competitions. Anybody who is transfer listed during the winter window has either fallen out with the manager or the fans or the owner and, more often than not, they are failing to perform to their potential.
Still, needs must and there are occasions where transfer business conducted in January can pay dividends. Let's take a look at the best, and worst, January transfer window signings that Chelsea have made.
The best players will have made a major positive impact on the club or have increased their transfer value. The worst have not done enough to justify their transfer fee or were unnecessary additions to the squad.
Transfer fees are from transfermarkt.co.uk unless otherwise stated. Statistics are from ESPN stats.