Gerrard is not playing in the hole behind the striker nor on the right of midfield anymore, positions where he would find space behind the defense or on the edge of the area; positions where he could score regularly. Now he's further from the box, providing the crosses and anchoring the build-up play; it would be unusual for him to score at the same rate as before. Were he playing where Meireles is now perhaps it would be him with 4 from the last 5 instead...