The Blues make the last eight but only after Watford took the lead. Nicolas Anelka was the hero; his hat-trick a master class in finishing.

Resolute Watford shocked their visitors from a higher league with a counter-attack goal on 69 minutes but the response began just five stressful minutes later and Chelsea domination throughout was turned into a fair result - eventually!

Guus Hiddink watched the game from high in the stands alongside Roman Abramovich, very much leaving control to Ray Wilkins and just how much would the side be altered was the big question before kick-off.

Fit-again Petr Cech came back in but the main news was a debut for Michael Mancienne, asked to play right-back in place of absent José Bosingwa. It was not the position most familiar to the 21-year-old for his debut but one he had played on loan at QPR.

Ivanovic stood in for suspended John Terry but the other big story was a starting line-up place for Didier Drogba for the first time since Old Trafford a month ago.

The Ivorian almost announced his comeback with a telling contribution inside 20 seconds, his cross from the right dropping just out of Kalou's reach. Wilkins had selected a front three with Anelka right wide and the newly crowned African Young Player of the Year on the left.

Drogba then drew a flying save from keeper Scott Loach seven minutes in after a typical turn and early shot from 25 yards.

Chelsea were pressing very high up a pitch that was already covered in plenty of divots. This would not be an easy day for running with the ball.

Alex met a Lampard corner on 10 minutes but at full stretch, couldn't keep his header down. Mariappa headed on target at the other end from a deep free-kick but it was a comfortable collection for Cech.

From a similar free-kick for Chelsea, Brendan Rodgers's men were caught napping but with three Chelsea men in behind the back line and unattended, Kalou failed to find a colleague as he headed back across goal.

On 18 minutes, Watford attacked down the Chelsea left but Ashley Cole looked to have found touch. Referee Mike Dean decided he'd fouled Tommy Smith in the process. A few second later a yellow card was produced, Cole's fifth of the season. He will be suspended against the pace of the Aston Villa attack next weekend.

On 25 minutes, stand-in skipper Lampard warmed Loach's hands with a stinging free-kick. All Chelsea's efforts were coming from outside the area.

Watford had a brief hope of a penalty on 32 minutes as McAnuff took on and drew a foul from Alex but the incident occurred just outside the area.

Two minutes later the Blues finally cut through Watford with a passing move. It had pace, it had precision and in a flash Drogba had put Anelka through. The shot was stabbed past Loach but bounced off the far post and was cleared.

Watford had the last chance before the break but in front of a crowded goal, Rasiak's header was pushed away by Cech.

Chelsea started the second half with intent. Loach pushed away a Drogba close-range effort and a thumping Lampard drive smacked into the hoardings having missed by not much.

On 59 minutes Mancienne, who had looked comfortable in this company, advanced into space and switching to his left foot, let fly with a Lampard-like effort, clearing the bar by only a couple of yards.

Before then Watford had failed to capitalise on their fourth corner of the game - all defended with man-to-man marking by Chelsea and Ashley Cole stood on the far post.

An hour in came the best chance yet and the worse miss. After Cole had got in the way of a Drogba shot, the ball fell Ballack's way but from inside the six-yard box, he scooped over the bar and fell back on the turf in despair.

Chelsea were dominant. Anelka had a shot deflected wide after Kalou penetrated and then Ballack headed wide as Lampard returned an overhit Drogba corner.

The last thing that looked on the cards at this stage was a Watford goal but as the home side defended a corner, both Ivanovic and Alex got sucked into challenges inside the opposition half. Watford broke and the makeshift backline was caught out.

Clear through, substitute Tamas Priskin kept his cool and his shot looped in via Cech's body. Suddenly, Chelsea had that Barnsley feeling.

Stoch on for Mikel was Wilkins's immediate response, the youngster preferred to the Quaresma option, but it was one of the old heads that took charge with Drogba and Anelka now playing together as a front two.

The Watford goal had come on 69 minutes and it took just five minutes to draw level. It was Ivanovic who nodded on Lampard's cortm and as the ball fell at the far post, Anelka with back to goal hooked in from little more than a yard out.

The next stage of the salvage operation was to hit Watford while they were down and as Cole crossed from the left, Anelka's header on the run was guided perfectly inside the post. In just two minutes Chelsea had turned deficit into advantage.

Still the Hornets' string had not been totally drawn. It took a good Cech save to keep out McAnuff on 90 minutes but it was the Blues turn to counter-attck with great effect. Stoch and Kalou combined down the left and when the ball was centred, Anelka's shot from 15 yards out was pin point. Game over. 

Chelsea (4-3-3): Cech; Mancienne, Alex, Ivanovic, A Cole; Ballack (Belletti 82), Mikel (Stoch 72), Lampard (c); Anelka, Drogba, Kalou.
Scorer Anelka 74, 76, 90+1.
Booked A Cole.

Watford (4-4-2): Loach; Hoyte, Mariappa, DeMerit (c), Doyley; Smith, L Williamson (Cowie 66), Jenkins, McAnuff; Rasiak (Priskin 66), Hoskins (O'Toole 75).
Scorer Priskin 69

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