The normally mild-mannered Zola was angry his side made so many mistakes on Monday night when they were beaten 3-1 at Manchester City.

That left the Hammers in the relegation zone ahead of Sunday's Upton Park derby with Fulham, who are also struggling.

Zola insisted he intended to get "on top" of his players until they "get it right" and Clarke was adamant the Italian was correct to do so.

He said: "I've seen him angry before - I've known him a long time. On Monday night we were all a little bit frustrated. It was a game where we didn't play as well as we have done.

"Decisions also went against us at certain times and it all added up to frustration.

"We have had a good week since then, the players have worked hard and we are looking forward to it.

"He is a very positive person who tries to transmit that to the group and he does that very well."

The Hammers have lost their last four games, including a Carling Cup knock-out at Bolton, conceding 10 goals.

Clarke added: "We haven't defended set plays as well as we have done previously so we have worked on that in training.

"Third from bottom is where we are right now so we have to rectify that on Sunday. That's where we are and we have to look at moving up from there.

"Hopefully we can prove we are in a false position - that's what we have to do."

Skipper Matthew Upson is expected to return following a calf injury and his addition to the centre of defence should help Zola and Clarke in their quest to make the Hammers tougher to beat.

He said: "Tougher is a mental thing. Everybody has to pull together and work harder.

"We lost a game on Monday night - it's not a disaster.

"Morale has not gone down as much as people think. The spirit is still good in the camp.

"We have a lot of good players, are a good unit and work well together. Monday was a disappointment we have to put behind us.

"If you lose experienced players it is always going to have a detrimental effect."

Midfielder Valon Behrami is back in the squad following injury but will not start.