Salomon Kalou came off the bench to fire home a second-half equaliser and prevent Everton derailing Chelsea's FA Cup defence in a 1-1 draw at Goodison Park.

The Toffees appeared to be heading to the last 16 after Louis Saha broke the deadlock in the 62nd minute of the fourth-round encounter with a tidy header from a Leighton Baines corner.

But Blues boss Carlo Ancelotti brought on Kalou 20 minutes from time and the forward did not disappoint as he decisively levelled the scores to set up a replay at Stamford Bridge and keep
 holders Chelsea in with a chance of retaining the trophy.

Chelsea, who have been causing unrest on Merseyside already this week with their so far unsuccessful bid to bring Liverpool ace Fernando Torres to the Bridge, were unable to spread that upset
 to the other side of Stanley Park in an sloppy opening half.

Everton made the brighter start on a crisp afternoon at Goodison Park but the first shot of the game came from the visitors as Ashley Cole found Didier Drogba to the left of the Toffees goal. The
 Ivorian striker took a chance from the edge of the hosts' box, but the tame effort was collected comfortably by Tim Howard.

The Blues built another assault down the left soon after as Cole made a charge, but some tidy, albeit slightly hurried, defending from Seamus Coleman kept the full-back at bay.

Attack

The Toffees responded with their own attack as Diniyar Bilyaletdinov surged down the left flank and swept in a strong cross beyond the far post, but Coleman failed to get under it close to the visitors' goal as the Blues defence intervened.

Bilyaletdinov was involved again minutes later as Everton got a chance. The Russian midfielder crept up on a dozing Jose Bosingwa in the aftermath of a Phil Neville throw-in, slipping the ball towards goal. Fortunately for the Blues, Petr Cech was more alert and scooped up the docile effort.

Howard was under pressure of his own when John Terry powered a dangerous header towards goal from a Florent Malouda corner, but the captain's effort scuffed just over the crossbar, prompting a sigh of relief from the home faithful.

Possession was an even 50/50 midway through the first half after a tight opening, with chances few and far between.

It was the hosts that were handed the first real opportunity 25 minutes in when Saha got away, fed by some solid work from Marouane Fellaini. The striker set up Jack Rodwell in a dangerous position but the Toffees man, under pressure from Ramires, failed to get enough power on his shot, which was easily parried by Cech.

The home side kept up the heat as Phil Neville lofted in a speculative cross from the right which Branislav Ivanovic should have dealt with. Cech was called into action again to make up for the stopper's blunder, blocking Bilyaletdinov's quick-thinking header.

Chelsea responded in force as Ramires released Nicolas Anelka with a well-judged pass in midfield. There was an intake of breath from the home crowd as the Frenchman stormed down the left and looked certain to slot home, but a brave, and crucial, save from Howard kept the visitors out.

More chances came from both sides in the late minutes of the opening half, with a lively-looking Coleman seeing his attempt from the box lashed behind, while a long-range effort from Malouda was always going wide without the help of Howard, who took no chances as he punched it further clear with a rolling save.

Everton were looking livelier and in control in the dying stages, with Saha proving a particular irritation for the visitors' defence as he came precariously close to goal several times in quick succession before setting up Mikel Arteta for a long-range shot, which went narrowly wide.

After a prolonged spell of pressure from the home side, Drogba looked determined to get something for Chelsea before half-time as he stepped determinedly up to take a free-kick from 40 yards in the Toffees' half.

But his powerful shot collided with the head of Coleman, lurking nearby, to keep the deadlock intact going into the break.

The hosts enjoyed an electric start to the second half as an impressive touch from Coleman set up Rodwell in the Chelsea half. Unable to escape Ivanovic, the midfielder turned tightly to feed an incoming Saha to the left of goal, but the Toffees man just failed to apply the finish as he slipped the ball narrowly behind the net.

Everton came agonisingly close again minutes later as an Arteta free-kick from 30 yards found the head of Fellaini, whose effort brushed tantalisingly over the woodwork.

Chelsea were looking sloppy and the Toffees seemed determined to take advantage, keeping the visitors firmly on the back foot. Arteta was at the centre of the action once again as he attempted a long-range shot, but the midfielder sliced it disappointingly wide.

After an intense spell of pressure from Everton all that was missing was the goal, and they did not have long to wait.

Saha made no mistake as he placed himself perfectly in front of goal to meet a Leighton Baines corner. The striker shrugged off the watchful Terry to unleash a fantastic header and bury the ball decisively past Cech and into the back of the net.

Ancelotti responded quickly by providing the Blues a fresh pair of attacking legs, bringing off Malouda for Salomon Kalou 20 minutes from time, and the manager saw his decision almost instantly rewarded.

Threatened

Some crucial defending from Essien kept out Coleman, who threatened with a second for the Toffees, and on the counter-attack Anelka released Kalou in midfield.

The forward chose to ignore the well-placed Frank Lampard and continue solo, jinking past a tackle to fire a well-timed shot just inside the far post to pull the Blues level in the 75th minute.

Ramires almost followed his lead with a long-range shot in the dying stages of the clash, but his venomous strike clipped the post.

Substitute Jermaine Beckford came close for the Toffees as the minutes trickled down, but neither side could find a winner, meaning David Moyes' men will have to wait for a chance to settle things on a trip to west London.

Everton	Team Statistics	Chelsea
1	Goals	1
0	1st Half Goals	0
6	Shots on Target	4
5	Shots off Target	6
5	Blocked Shots	1
11	Corners	5
9	Fouls	9
3	Offsides	2
0	Yellow Cards	0
0	Red Cards	0
83.8	Passing Success	81.9
23	Tackles	25
87	Tackles Success	64
49.7	Possession	50.3
56.3	Territorial Advantage	43.7

Teams 

Everton  Howard, Neville, Heitinga, Distin, Baines, Coleman, Arteta, Rodwell (Beckford 86), Bilyaletdinov, Fellaini, Saha
Subs Not Used  Mucha, Hibbert, Jagielka, Guey, Osman, Baxter
Booked 
Goals  Saha 62

Chelsea  Cech, Bosingwa, Ivanovic, Terry, Cole, Ramires, Essien, Lampard (Mikel 85),  Anelka,  Drogba, Malouda (Kalou 70)
Subs Not Used  Hilario, Ferreira, Bruma, McEacran, Sala
Booked 
Goals  Kalou 75

Attendance  28,376