The Scottish team will go in to the game 3-1 to the good in the tie, after they dominated their Slovenian opponents at Ibrox last week.
Despite their comfortable position going in to the match there are still doubts over the trio.
Ryan Jack missed the first leg last week due to a concussion injury but is due to return in time to line up, while Scott Arfield should also return after being rested in the Socttish Premiership over the weekend.
Lassana Coulibaly has been suffering from fatigue and will have to await a fitness test before the game.
"In terms of distances and high speed so I think it is just his body letting him know that he might need a little bit of a break at some point." Gerrard said.
"It is a big game Thursday and we will have to wait and see what he is like in the next 48 hours before we make a decision on him."