Juventus suffered a second consecutive Champions League defeat, falling 1-0 to Olympiacos with a stunning Roberto performance in goal.
Elsewhere, Atletico Madrid crushed Malmo 5-0, including a goal from Alessio Cerci, so the Spanish and Greek sides top the group with a three-point advantage over Juve and Malmo.
This was a head-to-head in Athens, as all four teams in the group had one win and one defeat going in. The Bianconeri missed Andrea Barzagli, Martin Caceres, Romulo and Luca Marrone, but Alvaro Morata and Arturo Vidal were picked rather than Fernando Llorente and Claudio Marchisio. The Greek side had to do without Jorge Benitez and Siovas, but dropped Ibrahim Afellay.
Juve adopted their all-blue away strip, scrapping the green version that had brought criticism in their 1-0 defeat at Atletico Madrid.
The hosts had an aggressive start and after six minutes Gigi Buffon flew to fingertip the Alejandro Dominguez free kick out of the top corner.
Juve had a great chance to take the lead on 11 minutes, as Morata’s header from an Andrea Pirlo corner was redirected by Carlos Tevez, but Omar Elabdellaoui performed a decisive goalline clearance.
Tevez had the ball in the net, but was offside when Stephan Lichtsteiner flicked on the corner. Dominguez threatened again with a smart half-volley flashed across the face of goal.
Pirlo gave the ball away repeatedly in midfield and was penalised for it when sparking an Olympiacos counter-attack, as it was pulled back for Patjim Kasami to side-foot into the near bottom corner. Kasami is no stranger to Juve, as he used to play for Palermo.
Pirlo’s free kick found Giorgio Chiellini, who on his weaker foot was unable to steer it towards goal from close range. The veteran went for goal on another set play, only to turn over the bar.
Sport Mediaset claimed that Juventus general manager Beppe Marotta went into the locker room at half-time to give the players a stern talking-to after that ineffectual performance.
After the restart, Lichtsteiner scuffed a volley not far wide, as did Luka Milivojevic, while Pirlo was substituted after hoofing a free kick off target.
Dominguez pulled back for Kasami, whose angled drive shaved a coat of paint off the base of the far post.
Tevez curled over, though Morata had a great chance when he combined with Tevez, spun round and forced Roberto into a reaction save from point-blank range.
Morata also nodded a Vidal cross over the bar and saw Botia charge down his shot in the six-yard box. Juve started to increase the pressure, as within 30 seconds first Roberto flapped a Paul Pogba cross-shot out from under the bar, then Vidal pulled back for Tevez and forced the goalkeeper to parry with his leg.
The Bianconeri moved to a 4-2-3-1 system for the final 13 minutes and Roberto again was alert on a Pogba cross-shot when Eric Abidal ducked out of the way.
The Olympiacos goalkeeper was decisive on the resulting corner, brilliantly palming a powerful Morata strike on to the bar with one hand. Roberto again got down quickly for another one-handed save on the Tevez daisy-cutter. Olympiacos held on for their fifth consecutive Champions League home win.
Olympiacos 1-0 Juventus
Scorers: Kasami 36 (O)
Olympiacos: Roberto; Elabdellaoui, Botia, Abidal, Masuaku; Maniatis, Kasami (Giannoulis 90); Milivojevic, Dominguez (Fuster 85), N’Dinga; Mitroglou (Afellay 69)
Juventus: Buffon; Ogbonna (Pereyra 77), Bonucci, Chiellini; Lichtsteiner, Pogba (Giovinco 87), Pirlo (Marchisio 57), Vidal, Asamoah; Morata, Tevez
Ref: Mazic (SRB)
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