Manchester City boss Kevin Keegan expects Sun Jihai to be out for a year after he suffered an injury during the victory over Chelsea.
"The idea for him was to play on Frank Lampard," said Keegan. "He did a great job and was arguably our best player up until he got injured.
"He is out for a year. he has done his cruciate and medial ligaments. It is a massive blow for him and us.
"We are a small squad. We have lost four midfielders now."