The Belgium midfielder, who has just returned from two months out with ligament damage in his right knee, winced after Fulham defender Timothy Fosu-Mensah landed on him as they competed for the ball.
The Belgian was making his first start for the club this season after spending two months on the sidelines with a knee injury.
Even though De Bruyne's period of convalescence will include an global break, he is still facing the prospect of missing seven games for his club, including the Manchester derby and a trip to Chelsea.
"We want him here, but at the end of the day it's him, agents and his family that decide", Guardiola said.
Although De Bruyne, whose wife gave birth to their second child on Wednesday, does not require an operation, he will fly to Barcelona to see specialist Dr Ramon Cagut. He knew that at the start of the season and wanted to stay. The Spain youth global will be out of contract in the summer and according to United Kingdom papers inclusing The Times and Telegraph, Real Madrid would be very interested in taking the player back to Spain. He understands the way we want to play. Their game was postponed this week following the death of Leicester's owner and four other people in a helicopter crash on Saturday.
"It was a hard situation because of the pitch and the conditions and tough physicality but today again he was involved in the offensive and defensive side, in the pace, in the set pieces, the passes and assists".