The champions struggled at Vicarage Road and looked set to fall eight points behind leaders Manchester United before Kalou scored.

Asked afterwards if Chelsea had to win the game to stay in the title race, Terry told Prem Plus: "We thought so.

"We thought we should get three points but if we are to push for the Championship we need to win at places like this."

Terry admitted the Blues had struggled to assert their superiority over Adrian Boothroyd's strugglers.

"It was a fight coming here and they made it very difficult," he added.

"We chased the game and thankfully Salomon popped up.

"I fancied us nicking one, we had some good chances today and I thought it was deserved."

Chelsea manager Jose Mourinho admitted his side had been seconds away from effectively conceding the title.

"I think so," he said. "Mathematically no, but if you go to eight (points behind Manchester United) it is much more difficult.

"It was a crucial goal and victory."

Mourinho praised Watford's effort but admitted he was surprised by their lack of ambition given their ever dwindling survival hopes.

"It was a very difficult game and we didn't play well, especially in the first half," he added.

"The pitch is small and bad, they fought and ran. I never like matches after international weeks because the players don't come back in the best condition.

"Only our belief gave us that chance. A draw would be a fair result for them because they fought a lot.

"I was surprised because one point for them means nothing - I thought they would play a different way, try to win."

Boothroyd was left to rue missed opportunities but claimed his side could draw comfort from the performance.

"We had the chances to win the game. We disrupted an excellent team," he told Prem Plus.

"But if you don't take your chances you will get punished.

"It's hard to take but we have to look at the positives and there were a lot today.

"We took a big step forward today as a group of people."

Defeat leaves the Hornets 11 points short of safety, but Boothroyd is not yet ready to accept relegation is inevitable.

"I won't be resigned," he insisted. "We will keep going to the death because we want to finish strongly and make sure we start strongly next season."