Borussia Dortmund travel to Italy to face Napoli in the first of their Champions League "group of death" matches. Schalke, meanwhile, have an easier home game against Steaua Bucharest to get the European ball rolling.
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Borussia Dortmund and Schalke were both poised on Wednesday to start their campaigns to reach this season's Champions League final in Lisbon next May. Coaches Jens Keller and Jürgen Klopp unsurprisingly chose probably the strongest sides available to them for their European curtain-raisers.
Dortmund traveled to Naples to face last season's Serie A runners-up Napoli, the first of six games in a devilish group also including Arsenal and Olympique Marseille.
With five wins from five matches in the German Bundesliga, Dortmund sit top of the table and have barely borken stride since the summer departure of Mario Götze. Fresh from a 6-2 win over Hamburg at the weekend, albeit where the Bundesliga runners-up looked shaky in defense at times, Dortmund's new attacking players have settled straight into the squad.
Gabonese winger Pierre Emerick Aubameyang had to make do with a spot on the bench, even after scoring a brace and setting up another two on Saturday.
Schalke favorites against Steaua
Dortmund's fierce local rivals Schalke were able to start their Champions League campaign with home support, as Romanian champions Steaua Bucharest came to Gelsenkirchen.
Teenager Maximilian Meyer had to make do with a spot on the bench - even on his 18th birthday - as Schalke put out their most potent attacking lineup. New signing Kevin-Prince Boateng, who rescued a lackluster Schalke with a splendid goal in their 1-0 win over Mainz at the weekend, was pencilled in at the central attacking midfield spot - with Jefferson Farfan and Julian Draxler on either side.
Prior to Boateng's signing, Draxler had sought to establish himself in the central position - but the Ghanaian international's arrival has again shuffled the deck. Coach Jens Keller said on Wednesday, however, that Draxler was actually quite happy to take a step back.
"Over the summer a lot of attention was raining down on Julian, he was standing right in the spotlight," Keller said, adding that the arrival of another big, experienced name was "doing Julian good."