The Hoops head into next Wednesday's second leg against Legia Warsaw at Murrayfield needing to overcome a 4-1 deficit to move a step closer to the group stages.
Ronny Deila's players were far from their best as they crashed to an embarrassing defeat and assistant boss Collins said: "It's going to take a terrific performance to get through. We'll have to defend well and we will have to take our chances.
"But there is no doubt we will create chances with the players we will have on the park.
"But are we going to take those chances we create? Of course we are.
"We need a great Celtic support behind us, pushing the players forward. The fans will play a huge part as well."