Sam Allardyce says he will wait until the last minute to make a decision over Diafra Sakho's fitness ahead of Saturday's Barclays Premier League game at Stoke City.
The Hammers head to the Britannia Stadium looking for a fourth straight win, but have doubts over Sakho after he injured his shoulder in last weekend's 2-1 victory over Manchester City.
The manager rates his chances of playing as touch and go, but says he has the players to cover should the Senegal striker not make it.
He told whufc.com: "We're going to have to wait until the last minute to make a decision on Diafra, because of the pain and movement that he has to get through and be comfortable with.
"Obviously the mobility of the shoulder is a concern, and we'll wait as late as Saturday morning to see if he's ready or not.
"There are lots of players desperate to get back in the team and that's the great thing about the squad with the injury list reducing.
"We've got the capability of hopefully coping with the loss of Sakho [if it comes to that], and not losing the level of performance we were showing.
"Our big problem is that he is our leading goalscorer, so somebody else might have to come in and take the chances he's been taking."
Big Sam says the biggest challenge facing his players this weekend is forgetting about their success against Manchester City and starting again from scratch.
He added: "Historically you would say that the team who was the underdog and beaten a top four team, statistically they lose the next game.
"I've been telling the players about the level of performance they will have to hit. The euphoria that went around us beating Manchester City and the effort the players put in, means that they have got to make sure they get themselves to that level again.
"Mentally they have to approach the game in the right way. All the hype behind playing Manchester City was build up by the media and the press, and with no disrespect to Stoke that won't be the same, so the players have to do it themselves, with me stimulating them to think that way in the last few days."
The Hammers will be backed by close to 3,000 fans at Stoke and Allardyce is keen to give them a happy trip.
He said: "Seeing the fans with smiles on their faces is what we do it for. Everybody comes to a football match or works in football for that kind of feeling. We're paid to entertain, we're paid to win and we're paid to put smiles on people's faces.
"The way that can happen is not always that easy because the level of money spent in the Premier League, compared to how it used to be, means sometimes it's a massive handicap to continue to do that.
"But hopefully we'll continue to do it for a considerable time for the West Ham fans, and most importantly at Stoke this weekend."