Manchester City made it ten straight wins in all competitions following a 3-1 victory at Swansea City, but their celebrations were marred after the Belgian suffered an apparent hamstring injury eight minutes from time.
“I think he is injured, that’s why we have to have a big squad as everyone will help us,” Guardiola told BBC Sport afterwards.
“Tonight we’re going back to Manchester, tomorrow the doctor is going to see him. It’s a pity – he is important for us. How he reacted, it looks like it was a muscular injury, but I’m not a doctor.”
De Bruyne has contributed two goals and four assists for City so far this term.