Drogba put Chelsea in front with a bullet header in the 71st minute but they had to settle for a point when Cahill’s spectacular overhead scissor-kick beat Carlo Cudicini from six yards.

Drogba’s goal was his seventh of the season and the point was enough to stretch Chelsea’s unbeaten home league run to 69 games.

While Chelsea had begun brightly, it was Everton who created the first clear cut chance of the game in the 15th minute when Leon Osman headed a cross from Ayegbeni Yakubu back into the path of Steven Pienaar.

However, under pressure from Michael Essien, Pienaar was unable to connect with the ball as it bounced dangerously in the penalty area.

Chelsea responded with a quick counter attack and Essien’s burst out of defence ended with a neat pass to Shaun Wright-Phillips on the right flank.

Unfortunately for Chelsea, Wright-Phillips could not deliver the required cross and his overhit effort eluded everyone in the penalty area before rolling out for a throw-in on the opposite wing.

Chelsea lost centre-half Ricardo Carvalho in the 26th minute when he fell awkwardly trying to head clear and he was replaced by Israeli defender Tal Ben Haim.

But despite the changes, Chelsea should have taken the lead in the 28th minute when Drogba’s cross found Frank Lampard at the far post.

The England international cleverly brought the ball under control before pulling it back for the lurking Wright-Phillips.

But the Chelsea winger’s shot was well saved by Tim Howard, who then kept Everton in the game seconds later with super stop to deny Lampard.

The England midfielder’s shot was destined for the top corner until the acrobatic Howard turned his effort around the upright.

Drogba then failed to test Howard with free header from Lampard’s resultant corner.

In the 33rd minute, Drogba had better luck when he climbed highest to meet a corner from Joe Cole.

But once again the towering frame of Howard was able to collect his header from just under the crossbar.

Three minutes later referee Alan Wiley penalised Phil Neville for hauling down Drogba at the second attempt but the Ivorian striker could not find the target with his 20-yard free-kick.

Neville finally earned the wrath of Wiley when he was booked in the 38th minute for leading with his elbow in a challenge on Ben Haim.

But Drogba squandered a superb chance to put Chelsea in front in the 45th minute. Wayne Bridge sped down the left flank before supplying Wright-Phillips.

The England winger turned and found Drogba unmarked on the six-yard box but the Ivorian completely miscued and the chance went begging.

Everton replaced Yakubu and captain Phil Neville with strikers James McFadden and Victor Anichebe at half-time.

In the 50th minute Cahill was a whisker away from scoring an own goal when he headed Lampard’s free-kick just inches wide of Howard’s right-hand upright.

Everton’s new attacking dimension gave Chelsea some cause for concern in the early stages of the second half and the home side lost their impetus as a result.

Chelsea’s final ball left a lot to be desired and they were often forced to shoot from outside the penalty area as Everton continued to stifle them.

Essien was forced to snatch at a shot in the 59th minute when he created an opening on the edge of the penalty area and his effort went well wide of the target.

Chelsea’s frustration was enough for Grant to make a further change in the 63rd minute when the disappointing Wright-Phillips was replaced by Salomon Kalou.

But moments later it was Howard who rescued Everton once more when a delightful chip from Lampard saw the American tip his effort around the post.

Everton lived even more dangerously from the corner when Howard punched the ball straight to Alex, whose shot was then cleared off the line by Tony Hibbert.

But the deadlock was finally broken in the 70th minute when Drogba rose unchallenged to head home a corner from Kalou.

However, Chelsea’s hopes of claiming all three points evaporated in the closing stages when Cahill stunned the home crowd two minutes from time.

Belletti failed to clear a shot from McFadden and the Everton midfielder sent his overhead kick into the roof of the net.