A below-par Chelsea side were held to a goalless draw away to Romanian champions CFR Cluj.
Blues striker Didier Drogba had a frustrating game and was stretchered off with what looked like a serious injury in the second half.
Eugen Trica and Alvaro Pereira threatened in the first-half for Cluj, while Salomon Kalou wasted a couple of chances for the visitors.
Trica clipped the post late on and Petr Cech denied Pereira with a smart save.
Cluj showed their 2-1 win in Rome was far from a one-off as they made life difficult for the visitors.
On this performance the Champions League debutants will be anything but pushovers.
606: DEBATE
But Chelsea will still feel this was a missed opportunity to take a firm grip on Group A.
The early signs were good with Drogba linking up well with Kalou inside five minutes, only for his team-mate to scuff a shot at keeper Eduard Stancioiu.
But it was a rare sight on goal as Cluj got men back, defended deep and cut off Chelsea's supply from the flanks.
They also showed plenty of ambition on the counter-attack, providing more worrying moments for Chelsea's backline than manager Luiz Felipe Scolari would have wanted.
He will have been alarmed at how Trica was allowed so much room in the box but relieved that the Romanian miscued in front of goal.
Drogba tried to put Kalou through on goal with a neat ball over the top, but again he lacked the necessary sharpness to test Stancioiu.
Pereira whistled a left-foot shot past a diving Cech but also just the wrong side of the post.
Chelsea threatened again when Frank Lampard picked out Drogba with a free-kick routine straight from the training ground, but the striker failed to connect cleanly in front of goal.
Nothing was going right for the Blues' Ivory Coast striker as he continually came off second best to some fully committed Cluj defending.
Scolari tried to offer Drogba more support with the introduction of Nicolas Anelka for Kalou at half-time.
But 12 minutes after the break, Drogba was forced off when he landed awkwardly trying to get on the end of a Florent Malouda cross.
He looked to be in severe pain as he stayed down for several minutes and was clearly in some distress as he was stretchered from the field.
Lampard had a couple of sights at goal as he looked to rescue Chelsea's evening, but he shot weakly and then produced a dipping effort too close to Stancioiu.
But it was the home side who looked the more likely to steal the three points in the dying stages, with Trica's shot edging the outside of the woodwork and then Cech had to be alert to deny Pereira's effort.
Anelka had a half chance at the other end and Lampard shot wide in the second minute of injury time, but a Chelsea winner would have been cruel on Cluj.
CFR Cluj: Stancioiu, Tony, Souza, Cadu, Pereira, Culio, Muresan, Dani, Dubarbier, Yssouf Kone, Trica (Didi 88).
Subs Not Used: Nuno Claro, Panin, Hugo Alcantara, Deac, Emmanuel Kone, Ruiz.
Booked: Pereira, Dani.
Chelsea: Cech, Bosingwa, Alex, Terry, Bridge, Mikel, Kalou (Anelka 46), Ballack, Lampard, Malouda (Di Santo 74), Drogba (Belletti 57).
Subs Not Used: Hilario, Ivanovic, Ferreira, Stoch.
Booked: Alex, Anelka.
Att: 22,000.
Ref: Florian Meyer (Germany).
BBC Sport Player Rater man of the match: Cluj's Tony (8.50 on 90 minutes).
Please note that you can still give the players marks out of 10 on BBC Sport's Player Rater after the match has finished.
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