 Complete the following phrase:  Drogba continued scoring goals but suffered an injury at the training ground and decided to have an operation on his knee. He was unable to play for four weeks and missed key games against Valencia, Arsenal and Liverpool. Drogba returned from injury to play in an FA Cup third round match against Queens Park Rangers and wore the captains armband for the last 30 minutes he was on the pitch, but that was his last performance for Chelsea before international duty at the 