At the venue where his ascent toward "special" status began, Jose Mourinho’s troubled season took another turn for the worse as Chelsea went down 2-1 to FC Porto at the Estádio do Dragão on Tuesday. Just as it had done in a 2-2 draw against Newcastle United last time out, a Willian free-kick appeared likely to rescue another point for Chelsea when the Brazilian canceled out midfielder André André’s effort just before halftime. But Chelsea could not hold firm, and defender Maicon snuck in a near-post header from a corner early in the second half to put Porto level with Dynamo Kiev on four points at the top of Group G.

While, after beating Maccabi Tel Aviv two weeks ago, Chelsea’s situation is still not nearly as dire as in the Premier League, where they sit in a lowly 14th spot, they will now be under pressure heading to Kiev to take on Dynamo next month. Having previously gone four matches without a defeat, this was a worrying sign for Chelsea that their early season struggles are far from at an end.

Mourinho had openly criticized his players ahead of a return to the club where he lifted the Champions League title in 2004. And he backed up his statement that there were no longer any “untouchables” in his squad by starting with captain John Terry, last season’s player of the year Eden Hazard and midfield fulcrum Nemanja Matic on the bench. Yet those who did start failed to deliver.

Despite the changes, one of Chelsea’s poorest performers this season, Branislav Ivanovic, retained his starting berth. And again he was exposed, this time in allowing Yacine Brahimi to breeze past him in the 39th minute, before Andre turned the ball in on the rebound after Asmir Begovic’s initial save.

Willian’s fine free-kick past an unmoved Iker Casillas with the final action of the opening half gave the visitors a foothold that in normal circumstances they’d be expected to capitalize upon. Instead, just seven minutes into the second half Maicon got in front of Ramires and Begovic was caught out at his near post.

While Diego Costa, back in the side while he serves his domestic suspension, struck the crossbar with a fine shot from 20 yards, there was no way back for Chelsea, who must now pick themselves up against Southampton on Saturday.