IT IS difficult to know what to say. Watford had more than matched the most expensively assembled team in the history of world football and looked like they may have had a big say in the title race, only to see it stolen at the very death.

Most of the best chances had gone to the home side and they made supposedly all-conquering Chelsea look decidedly ordinary only for Salomon Kalou's 93^rd minute header to win the game.

Aidy made fully six changes to the side beaten at Tottenham two weeks ago with DeMerit, Chambers, Stewart, Henderson and Kabba returning and Douglas Rinaldi making his first ever start in a yellow shirt.

It was a fair reward for the Brazilian who had impressed during his 20-minutes as a substitute at White Hart Lane.

Aidy had opted for a slight change in system with the front two of Henderson and Kabba often splitting wide, allowing Smith to come from deep behind them.

Mahon, Francis and Rinaldi formed a three-man central midfield spine to match up with Chelsea's trio of Lampard, Makelele and Ballack.

Watford made a very bright start in glorious spring sunshine, winning a corner within the first 30 seconds and almost going a goal up minutes later.

They had a decent shout for a penalty on three minutes when Tommy Smith spun and shot in the box and the ball appeared to be blocked by John Terry's arm but referee Rennie waved play on.

From the resulting throw in, Kabba had a spectacular overhead kick well saved by Cech after Henderson's flick had fallen kindly for the former Sheffield United striker.

Chelsea crafted their first good opportunity on nine minutes when Lampard's astute pass found Drogba in space in the box.

However, the Ivorian opted to square across goal rather than shoot and allowed Shittu to get a block in and clear the danger.

Rinaldi then produced a remarkable 60-yard run, skinning Carvalho and Terry, and he was bearing down on Cech when Makelele got a foot in and, in desperation put the ball narrowly past his own post.

From the resulting corner the ball dropped to Henderson who snatched at his shot and saw it whistle over the bar.

There was not much doubt that Watford had enjoyed much the better of the opening 20 minutes with the Champions forced to do more defending than they would have expected.

Damien Francis was the first man to go into Rennie's book for a foul on Ashley Cole on 23 minutes, although the Hornets' bench couldn't hide their anger at the decision.

But just to show how concentrations levels couldn't be allowed to drop, Watford owed their goalkeeper for a tremendous save which kept them level on 32 minutes.

Lampard's header from the edge of the box fell to an unmarked Drogba, eight yards out and in plenty of space. The African shot low but Foster was equal to and and instinctively pushed it around the post.

Chelsea had started to build a head of steam, forcing the home side onto the back foot for a spell but the Hornets had looked relatively comfortable when forced to defend.

There was another scare for the home side with two minutes left in the half when Cole found space on the left and tried to cross for Drogba.

Foster managed to stick out a foot and hack clear but Watford needed to get to half time with their clean sheet intact.

This they managed although the officials did their best to make it difficult, playing exactly double the two minutes of stoppage time that had been indicated and awarding the visitors a dubious corner during that period.

Half Time: Watford 0 Chelsea 0

Jose Mourinho had clearly been unimpressed with his team's first half effort and reacted by making a double substitution at the break, hauling off Geremi and Makelele and replacing them with Paulo Ferreira and Salomon Kalou.

The changes meant that Chelsea were playing with virtually four up front with Kalou wide on the left, Wright-Phillips on the right and Drogba and Shevchenko through the middle.

It was difficult to believe that Kabba hadn't put the Hornets in front after five minutes of the second half.

Henderson flicked on Mahon's long throw from the right and, after a scramble, Kabba shot from six yards out but put it wide with Cech having no chance.

Tensions were running high and it manifested itself with a flare up between the two managers on the sideline.

Watford thought they had won a corner but referee Rennie, never afraid of putting himself at the centre of attention gave Chelsea a free kick for a 'foul' on Carvalho.

The Portuguese defender looked to have gone down almost comically, and Aidy's disgust antagonised the Chelsea bench, provoking Mourinho to confront him. It was a good couple of minutes before calm was restored to the technical areas.

Chelsea made their third change on 57 minutes with Obi Mikel replacing Cole.

Five minutes later, it was all hugs between Aidy and Mourinho who had clearly made up during a stoppage in play!

It was the Watford manager who approached his Portuguese counterpart with a smile and a shake of the hand - all accepted in the manner it was offered.

Shaun Wright-Phillips went into the book on 65 minutes after scything down Smith who was breaking down the Watford left.

Another good chance came the Hornets' way on 67 minutes after a lovely link up between Henderson and Kabba. The latter charged down the right and his cross found Francis on the edge of the six-yard box.

Unfortunately, the midfielder couldn't control the ball and could only toe-poke a shot which Cech was able to field comfortably.

On 68 minutes, Watford made their first change, sending on Tamas Priskin for Henderson.

The game continued to switch from end to end and Chelsea came close a minute later after Ballack's fine pass picked out Wright-Phillips on the left.

The winger cut inside and flashed a shot just wide of Foster's far post.

Similar to what had happened in the first half, Chelsea were beginning to build a head of steam and have the lion's share of the ball but plenty of resolute work from Watford was keeping them at bay.

With 14 minutes left, Paulo Ferreira was the second visitor to be booked after fouling Priskin.

A golden chance for the visitors went begging on 77 minutes after a mis-control from Mahon allowed Lampard a clear run on goal.

Just as the England midfielder shaped to shoot, DeMerit emerged from nowhere to block and send the ball behind for a corner.

Lampard had looked certain to score, eight yards out with only Foster to beat but the American international did brilliantly to foil him and save his skipper's blushes.

With ten minutes left, Aidy decided to make his second substitution, taking off Kabba and replacing him with Hameur Bouazza.

Another excellent intervention from DeMerit kept Chelsea at bay on 83 minutes after Drogba crossed from the left and it looked to be dropping for Shevchenko.

The American, racing towards his own goal, managed to flick out his head and guide to ball to safety from a perilous position.

Chelsea were now almost constantly in possession, desperate for a goal in the knowledge that title rivals Manchester United had won 4-1 earlier in the day, but Watford were keeping their shape and not allowing the champions a sniff at goal.

Despite the visitors being on top, Damien Francis then had a fantastic opportunity to steal all three points for the Golden Boys in the 88^th minute.

Stewart's deep corner landed at his feet, unmarked but he could only shoot straight at Cech who managed to beat the ball to safety.

It was no great surprise to see that the officials had decided to add four minutes of stoppage time.

In the first of those minutes, Carvalho went into the book for a late challenge on DeMerit.

Just when we thought the Hornets had done more than enough to win a valuable point, Chelsea stole all three at the death.

Shevchenko picked the ball up wide on the right and crossed to the far post where Kalou stole in to head past Foster and unjustly win the game for the billionaires.

Difficult to find words to describe such heart-break.

Line Ups

Watford: Foster; Chambers, Shittu, DeMerit, Stewart; Smith, Mahon, Francis, Rinaldi; Henderson (Priskin 68), Kabba (Bouazza 80). Subs not used: Lee (GK), Doyley, Bangura

Bookings: Francis (foul)

Chelsea: Cech; Geremi (Ferreira 45), Terry, Carvalho, Cole (Obi Mikel 57); Wright-Phillips, Lampard, Makelele (Kalou 45), Ballack; Shevchenko, Drogba. Subs not used: Cudicini (GK), Boulahrouz

Bookings: Wright-Phillips (foul), Ferreira (foul), Carvalho (foul)

Attendance: 19,793