Torquay midfielder Ian Morris is set to resume training after a knee surgery more than a month ahead of schedule.
"He will train for the first time today [Thursday] and then we'll assess it from there," Ling told BBC Radio Devon.
"He's not going to be available for the weekend because that's going to come too quick."
Morris could be fit enough for Torquay's FA Cup first round tie at Chesterfield if he can regain his fitness.
"We've got a reserve game against Brighton next week and we've pencilled that in for him," Ling said.
"It's been a lot quicker recovery than we've expected, that's for sure," Ling added.
Meanwhile, the manager has told Gulls defender Chris Robertson that he will have to force his way back into the side after recovering from injury.
Mark Ellis took his place alongside Brian Saah in central defence.
"We've kept two clean sheets, two victories and I think Chris will have to be patient and go onto the bench," Ling said.
"If that was Brian or Mark or any other defender they would expect it to be the same way."
Robertson, 25, had been an ever-present in the Torquay side this season until his injury.
"I'm very, very pleased to have Chris fit, but the two results without him in the team have been positive and at the moment he'll probably have to play the waiting game and I'm sure he'll fully accept that," Ling added.