On top of that, John Terry finished the game holding his back and Alex also picked up a knock in a tough Champions League encounter in Transylvania.
Scolari will not know the full extent of any injuries until Thursday, although he hopes Ashley Cole will be fit for the weekend.
Drogba's right knee appeared to jar as he tried to get on the end of a Florent Malouda cross.
Scolari said: "It was not the pitch, there are normally some problems in the game, in training, so we don't say the pitch is bad. Sometimes it happens in football.
"I didn't see the challenge on Drogba. Injuries come in training and on the pitch. This is normal for players."