Paris St Germain were made to pay for their profligacy as a late goal from Samuel Umtiti earned Lyon a 1-1 draw at the Parc des Princes on Sunday.
PSG had led through Edinson Cavani's 20th-minute header but, after wasting a whole host of chances to double their lead, Les Parisiens were stunned when Umtiti equalised in the 84th minute after a rare Lyon foray forward.
Boos echoed around the Parc des Princes at the final whistle as Laurent Blanc's side's indifferent start to the season continued.
Last season's Ligue 1 winners are currently fifth with just two wins in their opening six matches.
The hosts made a solid start to the match but Yohan Cabaye wasted a clear-cut goalscoring opportunity in the 14th minute when he sliced wide after a fine Zlatan Ibrahimovic knock-down.
They were ahead six minutes later, however.
Full-back Lucas Digne found space on the left wing and his deep cross lingered in the air enough for Cavani to evade his marker and dispatch a diving header past Lyon keeper Anthony Lopes.
PSG continued to dominate and Serge Aurier went close moments later after robbing Corentin Tolisso but his speculative effort ended up in the side netting.
Lyon should have been on level terms on the half-hour mark when Arnold Mvuemba's powerful free-kick crashed into the crossbar but PSG stopper Salvatore Sirigu blocked Steed Malbranque's follow-up shot.
Cavani could only fire over with the goal at his mercy shortly before half-time so the hosts went into the break with a slender advantage despite creating numerous chances.
PSG should have doubled their lead 10 minutes after the restart but Blaise Matuidi's cushion volley from another exquisite Ibrahimovic knock-down just missed the target.
With Lyon creating little of note, PSG attacked almost at will and Lopes atoned for spilling a tame Thiago Motta shot by pulling off a superb last-gasp save to deny Ibrahimovic on the follow-up.
PSG, however, were left to curse not taking their plethora of chances with six minutes remaining as Lyon snatched a late equaliser.
PSG failed to clear a corner and, after the bout of proverbial ping-pong in the penalty area, Umtiti's deflected shot sailed past Sirigu and into the net to silence the home faithful.
In a frantic finale, Lyon could have snatched victory two minutes later when Clinton N'Jie's pass found Tolisso in space in the area but the defender could only blaze over with the goal at his mercy.
PSG midfielder Marco Verratti had the ball in the back of the net moments later, but referee Ruddy Buquet ruled that Lucas had impeded Lopes beforehand and the hosts ran out of time to fashion any more efforts on goal.
Laurent Blanc admits PSG are "not good enough" to repeat their dominance of last season but has dismissed talk of a crisis.
When the word 'crisis' was broached in his post-match press conference, Blanc responded scornfully: "You normally await the 'crisis' in November - there, you will have the crisis in October.
"We know the rules. When you are in a club like PSG, you must get results.
"We must be aware that we are not good enough to control matches the way we did last season and we have to throw ourselves back into our work."
Midfielder Blaise Matuidi was at a loss to explain what is happening to PSG - admitting: "We want to find a solution, it's hard to understand" - while striker Zlatan Ibrahimovic stormed away from a post-match video interview screened on L'Equipe's website.
The Sweden international was reminded he had spoken about "problems" with PSG after their Champions League game with Ajax - which ended in yet another draw - and was asked whether the Lyon game was any better.
"I said it was the problem in the field, and you talk about problems outside the field," said Ibrahimovic, adding as he walked away: "So either you talk about what I'm saying, or not."
Blanc, at least, was prepared to discuss the Lyon game and said: "The first period, although we were not as dominant as we were against St Etienne, was overall very good but the second period was very disappointing.
"The errors we made in the second half... we need to reflect on them a bit. We wanted to score another goal and we exposed ourselves to counter-attacks from 60 metres. There are times when you have to know to tighten up the game and settle for 1-0.
"We did some unbelievable things. From a corner, we tried a dribble instead of a shot and opened ourselves up to a counter-attack."
