Chelsea surrendered a first-half lead once more as we could only draw at Genk, missing a penalty as we let the hosts back into our Champions League Group E game.
It had all looked so straightforward when Ramires had advanced through a static home defence to fire Chelsea into a 26th minute lead, an advantage that should have been doubled when David Luiz took responsibility before the break, the Brazilian's spot kick saved by Genk goalkeeper Laszlo Koteles.
The miss would come back to haunt the Blues on the hour mark when striker Jelle Vossen levelled from close range, Genk's first goal in this competition, to earn his side an unlikely point.
The introduction of Frank Lampard to central midfield shortly after Genk's goal handed the initiative back to the Blues, but it was the England midfielder who would miss the best opportunity to win the game, getting his footing wrong as he failed to connect with a low Daniel Sturridge cross just feet from the Genk goal line.
Florent Malouda almost snatched it for Chelsea at the death, but in the end we had to settle for a draw, and further question marks over our defending under pressure.
The draw is no disaster in the context of Champions League qualification however, with Bayer Leverkusen beaten at Valencia, leaving us still in command at the top of Group E.
Such was the strength of our position in this group, Andre Villas-Boas was again able to rotate his squad and still feel confident of achieving a result.
John Terry and Frank Lampard were both rested but available from the bench with David Luiz recalled to defence, while Raul Meireles started in midfield with Oriol Romeu in for the injured John Mikel Obi.
Chelsea were in the all black away kit, which for the first time featured the Right to Play logo across the back, a feature recently permitted by Uefa.
In spite of their 5-0 thrashing at Stamford Bridge a fortnight earlier, Genk started the game playing the better football but visibly lacked the killer edge that Robin van Persie had shown against the Blues just a few days earlier. As a result it was Koteles, the home goalkeeper, who was called into action first when Ramires poked a shot goalwards from the edge of the box in the ninth minute.
That move prompted Chelsea to take a better grip on the game, threatening down the left through the old combination of Malouda and Cole, with Meireles gaining plenty of ball-time in central midfield.
While Meireles sat in the centre, his midfield partner galloped forward and it was Ramires who would open the scoring for Chelsea after 25 minutes, taking control of a loose ball after some sloppy Genk play and driving on, exchanging passes with Torres before shooting low through the legs of the keeper from a tight angle.
As at the Bridge, the Belgians had created their own problems, and they nearly worsened on the half-hour when Torres flashed an effort just wide from 25 yards, and Ramires headed a Cole cross wide of the post.
An exquisite Chelsea move involving Cole and Meireles sent Malouda into the area with space to pick his pass, but his Torres-bound ball was cut out by Khaleem Hyland, who had to hold his breath to see the ball drop wide of the post for a corner. Villas-Boas's side were in complete control as half-time approached.
Wave after wave of Chelsea attack continued. Meireles struck the angle of post and bar after David Luiz and Torres had teed him up, and then came a chance to kill the game.
Malouda attempted a cross but at close quarters the ball struck Thomas Buffel's arm - penalty to Chelsea.
David Luiz stepped up confidently and struck cleanly, but Koteles guessed correctly and palmed the ball away low to his right. It would prove a frustrating moment after half-time.
Genk's Kevin De Bruyne passed up the opportunity to advertise himself to potential suitors when he scuffed a decent chance five minutes after the break, following patient right to left build-up from the home side. Chelsea were rumoured to be interested in the winger this summer, having already signed his former team-mate, the goalkeeper Thibaut Courtois.
Cech had to dive bravely at the feet of Kennedy Nwanganga to preserve Chelsea's lead a couple of minutes later after the back four went missing with the ball bouncing around the away side's penalty area.
A couple of corners had the home fans in the mood too as they willed their side forward once more, and their reward would arrive on the hour.
Fabien Camus, absent at the Bridge, strode into the area down Chelsea's right and pulled back into the danger area where forward Jelle Vossen stroked the ball beyond Cech and into the net.
Whether it was the shock of conceding or the changes brought by the manager, Chelsea began to wrestle control back from the hosts and Meireles could have headed us back into the lead when he met a Malouda cross, instead heading straight at the goalkeeper.
Lampard missed an even easier one on 78 minutes when Sturridge ploughed into the box and crossed low, the midfielder failing to make contact with the ball despite having a good view of the incoming delivery.
At the other end Cech had to advance off his line again to stop substitute Anthony Limbombe sliding Genk into an unlikely lead after De Bruyne had weighted a smart pass through the channel, but as the clock ticked over the 90-minute mark it was Malouda who could have snatched a win for the visitors.
The Frenchman did everything right, lifting the ball over Koteles from the tightest of angles, but between them the two covering defenders managed to scramble the ball behind for only a corner.
It was the last chance in a game Chelsea will feel we should have won, but could still have lost. The task for the manager is to rebuild confidence before Saturday's awkward-looking trip to the Premier League's bottom side, Blackburn.
Genk (4-4-2): Koteles; Vanden Borre, Hyland, Nadson, Ngcongca; Buffel (Ndabashinze 68), Camus, Tozser (c), De Bruyne; Vossen (Barda 86), Nwanganga (Limbombe 81).
Unused subs Sandomierski, Sarr, Durwael, Ofori-Appiah.
Goals Vossen 60
Booked De Bruyne 75
Chelsea (4-3-3): Cech (c); Bosingwa, Ivanovic, David Luiz, Cole; Ramires (Lampard 65), Romeu (Mata 76), Meireles; Anelka (Sturridge 65), Torres , Malouda.
Unused subs Turnbull, Terry, McEachran, Kalou.
Goals Ramires 25
Booked Meireles 90