Manchester City have been dealt a blow after German midfielder İlkay Gündoğan sustained a knee injury that manager Pep Guardiola fears will sideline him for "several months". The Turkish-origin Germany international had to be substituted in the 44th minute of City's 2-0 Premier League win over Watford at the Etihad Stadium on Wednesday after an accidental collision with Nordin Amrabat. Guardiola revealed afterwards he had sustained suspected knee ligament damage."We are going to miss him for a long time," said Guardiola. "This is the worst news. "I'm so so sad. The doctors think he has ligament damage, but he doesn't know exactly (how serious it is). "We will know tomorrow (Thursday), but it doesn't look good. I think it will be several months. He is so sad about it."Gündoğan, 26, joined City from Borussia Dortmund in June for a reported fee of 20 million pound ($25.1 million). He had dislocated his kneecap in May while training with Germany, which ruled him out of Euro 2016. Spinal surgery had previously cost him the entire 2013-14 campaign. Initially sidelined after undergoing surgery at the end of last season, he has impressed since making his debut in a 4-0 Champions League win over Borussia Moenchengladbach on September 14. To date Gündoğan has made 15 appearances for City in all competitions, scoring five goals. His injury cast a long shadow over a home victory for City - their first since beating Bournemouth on September 17 - that was secured by goals from Pablo Zabaleta and David Silva.