Huub Stevens' side took time to settle into their rhythm, but having assumed control rarely gave their hosts a sniff of goal thereafter. Benedikt Höwedes opened the scoring just before half-time and though Djamel Abdoun pulled Olympiacos level, Klaas-Jan Huntelaar, who would subsequently hit the post with a second-half penalty, was on hand to score the winner.
Höwedes heads Schalke in front
The Royal Blues started the brighter of the two sides, but soon found themselves pinned back by the hosts' precise possession play and passing. Paulo Machado broke in behind Schalke's backline inside five minutes, but having seen his initial effort cleared off the line by Kyriakos Papadopoulos, the winger could only ruffle the side netting with his second bite at the cherry. Klaas-Jan Huntelaar and Rafik Djebbour traded powerful headers that flew wide of the target, yet a lack of quality in the final third prevented either side sustaining a threat in front of goal.
Approaching half-time though Schalke thought they had gone in front when Papadopoulos headed in from close range against his former club. However, referee David Fernandez Borbalan adjudged the Greek centre-back to have fouled Balazs Megyeri in his attempts to win the ball. The decision sparked the visitors into life and minutes later Höwedes lost his man at the front post to meet Jefferson Farfan's corner with a thumping header, sending Schalke in a goal to the good at the break.
Fast and furious
Schalke picked up where they left off in the second half and should have extended their lead when Tranquillo Barnetta blazed over the bar from six yards after Christian Fuchs' long-range effort wasn't dealt with by Megyeri. Olympiacos pushed forward and, seconds after they twice had efforts cleared off the line, made the most of Schalke's defensive frailty. Papadopoulos failed to deal with a long-ball forward, which fell kindly to Abdoun, who swept the chance under Lars Unnerstall to level the scores.
However, the Royal Blues responded immediately to restore their lead as Lewis Holtby played in Huntelaar to crash an effort in off the far post. A foul on Barnetta inside the box should have seen the Dutchman add to his tally from the spot less than a minute later, but on this occasion the left post prevented his effort from finding the back of the net. Schalke kept things tight while making Olympiacos chase the ball late on and though Ariel Ibagaza and Huntelaar both went close to adding to the scoreline it was Schalke who opened their Champions League campaign with a win.
Olympiacos: Megyeri - Torossidis, Contreras, Manolas, Holebas - Modesto (Greco 69'), Maniatis - Abdoun (Mitroglou 69'), David Fuster (Ibagaza 58'), Paulo Machado - Djebbour
Schalke: Unnerstall - Höwedes, K. Papadopoulos, Matip, Fuchs - Neustädter, Jones (Höger 90') - Farfan (Draxler 90'), Holtby, Barnetta (Afellay 79') - Huntelaar
Goals: 0-1 Höwedes (41'), 1-1 Abdoun (58'), 1-2 Huntelaar (59')