Relegation-threatened Ipswich Town held Chelsea to a 2-2 draw at Stamford Bridge on Sunday, denying the hosts the chance to inject fresh momentum into their bid for a place in next season's Champions League.
The visitors stunned Enzo Maresca's men when they stormed into a 2-0 lead with just over half an hour on the clock, despite being pinned in their half for the early stages.
Ipswich's Paraguayan striker Julio Enciso nipped in between Chelsea's defenders to steer home a cross by right back Ben Johnson in the 19th minute.
Twelve minutes later, Enciso repaid the favour, crossing for Johnson to head home. Chelsea struggled to revive their momentum, prompting loud boos from the home supporters at the halftime whistle.
An own goal by Axel Tuanzebe immediately after halftime gave Chelsea hope and substitute Jadon Sancho curled a shot into the top corner in the 79th minute to set up a frantic finale when both sides came close to snatching a winner.
Ipswich goalkeeper Alex Palmer saved a Trevoh Chalobah effort at point-blank range in the 85th minute before denying Enzo Fernandez and Cole Palmer in time added on.
The draw pushed Chelsea into the last of the five Champions League spots but they are only one point ahead of Newcastle United who were playing Manchester United later on Sunday and have a further game in hand.
Chelsea had won their previous five home league games but have not won away since December, a run which included a shock 2-0 defeat to Ipswich at their Portman Road stadium.
The Londoners now face tougher opposition - including Liverpool and Newcastle United - in their final six games of the season.
Maresca rued defensive mistakes for both of Ipswich's goals and his side's failure to turn their early dominance - when Nicolas Jackson hit a post - into goals.
"I think we started quite well, creating chances, then when they scored the first goal the game completely changed," the Italian said.
"It's tough because even in the first 20 minutes, at this stage of the season, if you are not able to score the first one, then the game completely changes."
Ipswich remain in 18th place and are almost certain to return to the second tier next season. They are 14 points adrift of West Ham United, who are just outside the bottom three, with only six more games to play.
Ipswich coach Kieran McKenna said the gulf between his side - which won promotion to the Premier League only last year - and more established top-flight clubs had been too big, and he also rued a latest failure by his players to hold on to a lead.
"It looks like too much of a mountain for us this season in terms of picking up the points that we would have wanted," he said. "We've not been too far away from it, but it looks like we're not going to be able to climb that mountain."