Sakho injured his shoulder in the 2-1 victory over Manchester City and is battling to take part in the visit to the Britannia stadium.
“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,” Sam told the official site.
“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.”