Lampard shows his frustration as Chelsea falter at Stamford Bridge
Chelsea produced a far from convincing display at Stamford Bridge as they were held to a goalless draw by Everton that all but ends their title challenge.
The hosts enjoyed all the possession, but Everton had the better chances.
Jo twice fluffed when through on goal, while Leighton Baines was denied a penalty when he was fouled by Alex.
At the other end Didier Drogba shot onto the bar, but otherwise the hosts were pretty toothless and they now lie six points behind Manchester United.
The league leaders also have a game in hand over Guus Hiddink's side, meaning the Blues' hopes of silverware this season must surely now rest on the Champions League and FA Cup.
Their success in the latter, of course, will come down to their final against Everton - and the stalemate at Stamford Bridge will only fuel the Toffees' belief that they can compete with Chelsea on 30 May.
There was some suspicion before kick-off that it would be a good time to play Everton, following the Toffees' FA Cup semi-final exploits at the weekend and with qualification to next season's Europa League all but guaranteed.
Hiddink admits Chelsea title chase is over
However, for all their possession, it was Chelsea rather than the visitors who appeared to lack verve and spark in the attacking third.
Some cause of that was possibly Guus Hiddink's decision not to freshen up the side that beat Arsenal at Wembley on Saturday, but credit also to Everton, who got their tactics spot on.
Defending deep and in numbers, David Moyes's side allowed Chelsea plenty of possession up until 30 yards from their goal, at which point they nullified the Blues' threat and ensured a relatively quiet night for keeper Tim Howard.
Frank Lampard and Michael Essien tried their luck - unsuccessfully - from range in the first half, but it was the other end that saw the clearer chances.
Twice Jo was sent clear on goal, first by Tim Cahill and then by Steven Pienaar, but first the Brazilian shot straight at keeper Petr Cech and then he slipped at the vital moment, fluffing his effort wide of goal.
And Everton also had a big penalty shout when Baines went over Alex's outstretched leg, but referee Mark Halsey was unmoved.
The appeals were strangely muted from Everton, but TV replays suggested the Chelsea defender was lucky to get the decision.
It ensured the Blues entered half-time on level terms, but if they had hoped to use the break to collect themselves, it failed, with Everton picking up where they left off after the interval when Lars Jacobsen set Tim Cahill up to force another Cech save with a diving header.
Moyes pleased with Everton resilience
Chelsea again dominated the ball, with Everton happy to play on the break, but Howard remained little more than a spectator despite the Blues' increasingly desperate forays into the area.
With the hosts looking increasingly impotent up front, it was left to the unlikeliest of sources to force their best effort to that point, John Terry unleashing a 40-yard piledriver that Howard tipped wide.
And when Chelsea did eventually find room in the box - twice in a minute - first Yobo blocked Lampard's goalbound effort and then Salomon Kalou headed narrowly over.
The hosts did launch a late rally, with Everton defending desperately at times to keep out the likes of Alex, Drogba and Lampard.
And Drogba went agonisingly close with the hosts' best effort of the night in the 93rd minute when he turned brilliantly in the box and crashed a beauty of a shot onto Howard's crossbar.
However, Cahill and then Pienaar also had pot-shots at the other end and when the final whistle went it was hard to argue that a draw was the right result.
Everton manager David Moyes:
"I thought we played extraordinarily well, passed it beautifully and made a few chances, as well as having a good shout for a penalty.
"You come to Chelsea and you know it'll be a tough game and they made it hard for us at times in the second half, so you can't be too disappointed with a draw.
"They have other fish to fry with the Champions League and so on so maybe they had their eye off the ball this evening, but we certainly didn't and I'm happy with how we did against them."
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