Holland told chelseafc.com: "With regards to Didier his last moment with Chelsea was scoring the winning goal in the Champions League final. He left Chelsea at the top of European football. He went on to have two successful seasons with Galatasaray where they had good runs in the Champions League on both occasions.
"We are very happy to have him back. He's a leader and a proven match winner. Whether it's starting games or coming on from the bench we are all very confident he will play a significant part in Chelsea's season."
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