Speaking shortly after his side had suffered their first defeat in the month of December at the hands of Salford City, Clarke confirmed that Rory Holden will miss Tuesday evening's clash with Scunthorpe United.
"We'll get it assessed, it's his knee, so we'll se how that goes, but I'm very, very, very unlikely to be featuring (him) in any part of the Christmas period."
There is no doubt the loss of Rory will be felt across the team but now is the time for one of his teammates to step up to the plate and make the position their own, as the fixtures continue to arrive at quite a rate.
Holden was not named in the squad for Saturday's defeat to Salford after suffering what Clarke confirmed to be a knee injury following an innocuous challenge during training on Wednesday.
The former Bristol City prospect has been one of the Saddlers' top performing players over recent weeks and his absence was felt during the defeat to the Ammies as the Saddlers lacked a bit of creativity in attack.
Clarke also confirmed that Rory, a former loanee who joined the Saddlers from the Robins on a permanent deal in the summer, will be further assessed but didn't offer an estimated time as to when he may be able to return to action.
Speaking to BBC Radio WM's Tommy Marlow, Clarke said; "Rory Holden picking up an injury in midweek hasn't helped. Because I think has that that bit of quality in the final third that we missed today."
When asked about the prognosis, Darrell said; "Rory's going to struggle. (It was an) innocuous challenge on Wednesday. (I'm) very disappointed.
"We'll get it assessed, it's his knee, so we'll se how that goes, but I'm very, very, very unlikely to be featuring (him) in any part of the Christmas period."