WEST HAM number two Steve Clarke has urged his players to cut out the errors and start to impose themselves on games.

The warning comes after the Hammers suffered their third straight loss against Bolton on Tuesday, in a result that sees them slip to 19th in the table.

Things don't get any easier for West Ham as next up is the visit of league leaders Chelsea on Sunday. And Clarke has moved to warn the players against the mistakes that are costing the dearly, highlighted by Robert Green's blunder at the Reebok, when Ivan Klasnic pounced after England's number one keeper inexplicably spilled Gary Cahill's shot into the striker's path.

“You have to utilise the players you have in the best way,” said Clarke. “We have a manager who likes to pass the ball and when I say aggressive, you have to be aggressive with the ball and impose your style of play on the game. First half (against Bolton) we didn't do it, second half we did it much better. Unfortunately the game went away from us.

“I think if you start to rely on luck it will never come. We have to work harder, we have to be more aggressive, we have to play better, we have to cut out the mistakes and I think the harder you work the luckier you get and that's the philosophy we have to take.”

Clarke and manager Gianfranco Zola welcome their former club to Upton Park this weekend, and it is not difficult to predict who the favourites will be. But Clarke refuses to approach the game with anything less than a positive attitude.

“I thin it's a great game for us,” he added. “Nobody expects us to get anything and they have to go there and work as hard as they can. In football you never know. Because if you had said last week that Wolves would go to Tottenham and get a result you would have laughed. Maybe it will happen for us this weekend. That's what we're hoping for.”