The former Leyton Orient boss has been missing for the last four games due to a debilitating illness and doctors remain unsure of the cause.
Assistant manager Shaun Taylor has been in charge of the last four games in Ling's absence and he will take charge again at Spotland.
Taylor looks likely to continue in that role until the end of the current campaign and the club are looking for an experienced coach to assist the former Swindon centre-back.
The Gulls are expected to include Rene Howe in their squad for the long journey after their top scorer completed his two-match ban for 10 yellow cards.
Elliot Benyon looks set to be involved again after the Southend loanee played 45 minutes in Tuesday night's defeat to Rotherham while Taylor will hope to have Nathan Craig available after the Welshman came off at the break at Plainmoor in midweek.