The Reds lost the first leg 3-1 at Anfield and will need their inspirational captain fit and firing to be any chance of overcoming a tenacious Blues outfit.
"Steven is getting better, he will train with the squad and we will make a decision nearer the match," said manager Rafael Benitez.
"Obviously we want him in the side, winning is easier with him than without him.
"Everything can change if he can play, and plays well, and it is not a massive risk if we use him.
"If we lose a player for 10 to 14 days it will be bad, but that would only maybe effect one game for us. It is a calculated risk.
"The experience of Istanbul will help us, it shows you can come back from a big score. And it is important to realise that Bolton scored three there on Saturday, anything can happen.
"Steven is important, a key player for us. He has power and he can score goals."