The Hoops have endured a difficult start to the campaign, with defeats to AC Milan and Barcelona leaving them bottom of the section.
Back to back games against Ajax will prove crucial to any chance of reaching the knockout stages for a second successive year.
McNeill, who captained Celtic to European Cup success in 1967, said: "I still see the possibility that Celtic can get themselves into the next stage.
"I think when you look at the teams they are playing they are doing not too badly."
The Scottish champions were dealt a blow this week with the news that Adam Matthews is expected to be out of action for up to three months.
The Welshman is set to undergo shoulder surgery and will play no further part in the group stages of the Champions League.
McNeill said: "Injuries to any quality player can be difficult.
"But, looking at what Celtic have got, they are not too badly off. Hopefully they can get over it."
Meanwhile, McNeill has urged boss Neil Lennon to remain at Celtic for the foreseeable future and resist any temptation to move on.
He said: "I would prefer to see him stay with Celtic to be honest. He does a really good job.
"You can never tell whether at some stage he will go elsewhere but I hope not."