Mourinho talked of Schalke 04’s height in the box as being a danger going into the game but it was Chelsea’s physicality which was to tell in the opening exchanges in Germany.
Chelsea captain John Terry put the 2012 Champions League Winners ahead with this header from a corner.
The Blues have been deadly from set-pieces so far this season with Cesc Fabregas’ delivery playing no small part in this form.
Chelsea will qualify for the next round with a win or a draw against Schalke once there are no more than two goals on each side.
Schalke will reach the last 16 with a win in combination with a draw between Sporting and Maribor.