De Bruyne missed the majority of the opening two months of the season with a knee problem, but the 27-year-old's outing against the Cottagers had represented his fourth appearance since making a comeback in October.
His exit would be another blow for City, who lost Jadon Sancho to Borussia Dortmund in similar fashion last year, with the 18-year-old now a senior England global. "We want him, but at the end it doesn't depend on us".
De Bruyne, who played a pivotal role in City's record-breaking Premier League title triumph last term, has already spent six weeks on the sidelines this season. Nobody likes injured players.
Manchester City have been rocked by the news that influential midfielder Kevin De Bruyne is set to miss the next six weeks of action after suffering a knee injury during last night's 2-0 win over Fulham in the Carabao Cup.
Khashoggi's son shakes hands with Saudi royal blamed for father's death
Mr Erdogan also questioned why Khashoggi's body had not been found even after Saudi authorities admitted to his killing. But he suggested responsibility lay higher up: "Well, the prince is running things over there more so at this stage".
He doubled the lead in the 65th by slotting a shot high into the net from close range after Gabriel Jesus' curling effort came back off the post.
"He knows the desire we want for all young players", Guardiola added. "It is what it is but fortunately it is not surgery and he will be back".
The Manchester City squad were out in full force ahead of Sunday's Premier League game against Southampton. The doctor said he was sad - today he was less sad and the next day he'll be strong again.
"He can spend time with his new boy and his family and, after the global break, two or three more games and he will be back". We will do absolutely everything to keep him with us - afterwards, he decides.