I've only played the demo for 2011, and obviously I could only get to the beginning of January, but Chelsea do need a right winger that can go straight into the starting 11. I previously said Robben, but he begins injured for like 8 months. Perhaps look for a young player.
Maybe even train either Malouda or Zhirkov to player there, and have the other on the left. Kalou is an option, although not very good. These are a few options to not spend money..