Schalke remain unbeaten in the Bundesliga this season following a 2-0 away victory over Greuther Furth on Saturday.
The Royal Blues created the first chance of the game in the 12th minute when Julian Draxler headed over the hosts' crossbar.
The visitors continued to dominate proceedings in the first half and could have taken the lead just before the break had Klaas-Jan Huntelaar not missed the target from a good position.
Schalke finally broke the deadlock three minutes into the second half when Draxler cut in from the wing and shot home from 30 yards out.
Huub Stevens' side found the target for the second time in the game on 88 minutes when Lewis Holtby scored from close range.
It could have finished 3-0 to Schalke had Jefferson Farfan's effort in the dying seconds gone in and not come off the post.
