The Blues claimed a crucial advantage in the tie thanks to goals from Mason Mount and Ben Chilwell.
They were slightly rocky at the back, despite keeping a clean sheet, and the absence of Silva may have contributed to that.
"No, absolutely no problem (with Antonio Rudiger - involved in a training ground bust up)," Tuchel told BT Sport.
"He only had half an hour (Thiago Silva), and all the other guys are totally fit, so it's not the moment to improve your fitness level in a quarter-final.
"We trust the guys and we are clearly aware that we need a 100 per cent physical level.
"Thiago is a super important player but is not fully fit for 90 minutes at the highest level and we decided for the back three."