The Citizens currently hold a 2-1 aggregate lead over Zinedine Zidane's side following a dramatic victory at the Bernabeu, but the coronavirus pandemic has left the remainder of the tournament shrouded in uncertainty.
Nevertheless, Silva is hopeful about City's hopes for Champions League glory but insists that the Premier League champions will not get complacent at the Etihad.
"It's all very open. When you play a side like Madrid nothing is ever certain. We've seen a lot of ties in the last few years get turned around," Silva said in a Q&A with AS.
"You never know. It's a good result and we're in a great position to go through to the quarter-finals. It's a tough match and we'll need to play well and maintain our concentration.
"In the last three years we've won everything in England. Last season we won all four English titles, this year we've won the Super Cup and the League Cup, we're still in the FA Cup and we want to win that.
"But the Champions League is the title the club, the players and Pep Guardiola in England want to win. We know it's a tough tournament, but we'll fight for it.
"You can't write any team off, far less Madrid who have won 13 European Cups. No one else has the experience Madrid's players have in this competition, so we can't think we've already beaten them."
Silva, who played 73 minutes of City's victory in Madrid, has chalked up seven goals and eight assists in 39 matches this term.