Speaking at the Polish Army Stadium ahead of tomorrow night's clash, the Ibrox boss paid tribute to Legia, saying: "They are very-well organised, and they don’t concede many goals.
"I believe Legia will be aggressive tomorrow and try to press us high, certainly in the early stages so, while we will have to handle that, cope, and be able to handle the ball under pressure, that should give us opportunities to go and strike in the space behind."
Legia have only lost two of their last 15 matches, one of which was a friendly, and have former Scottish Premiership duo Radoslaw Cierzniak, formerly of Dundee United and ex-Hearts midfielder Arvydas Novikovas in their squad.
They defeated Europa Point of Gibraltar, KuPS of Finland and Greek outfit Atromitros en route to the play-offs, and Gerrard is only too aware of the Ekstraklasa side's strengths.
“The important thing for us is to keep creating chances because we have players in good form, and whatever the test and the challenge in front of us, we always have confidence and belief we can go and strike when the time comes in the game," he added.
"This will be a tough test and two close encounters over both ties. We have two good teams fighting for the same prize. I have big belief and I back my players to deliver.
“I think my experience of this team is when the challenge gets tough, they stand up and the hostility here in Legia will bring the best out of my team and I have every confidence we can get the result we need.
“Having said that, I don’t think this tie will be decided tomorrow. I think it will go to the wire.”