The former Reds striker is in line for a full debut against his old club.
Klopp said, "We know him very well and that's the problem, we know how good he is.
"He used to be our boy and it means I always wish him a nearly perfect Premier League season, that's 36 world class game and two days off - that's when we play them.
"We have to be 100% focused if he plays, but not only him. It will be an intense game.
"If he is on the pitch we know we cannot let him finish. He is a natural finisher and that is his biggest threat."