So says injury expert Ben Dinnery, who runs the Premier Injuries site and has a background in medicine and data analysis.
Jullien has returned to first-team training after a 10-month absence enforced by a knee ligament injury.
But Ange Postecoglou told the club’s media team on 22 October that he would not be available for selection until after the international break.
Dinnery claims that it will be “massively upsetting” for the defender to see his absence extend to 11 months.
But he maintains that Celtic are smart not to be too hasty when it comes to the Frenchman’s rehab.
He told Football Insider correspondent Adam Williams: “It’s always going to be difficult when you’re in the gym and training on a one-to-one basis.
“You’re missing out with the banter and if the team is doing well, you want to be a part of it.
“The initial timeline with his injury was in and around four months, and now we are approaching 10 months.
“The important thing with any long-term injury is to yourself small goals. Rather than looking to the end, it’s all about small motivating factors.
“It will be dispiriting, but it needs to be contextualised. It’s a risk and reward strategy.
“You would rather have an extra month out than risk returning too early and putting yourself out of action for even longer.
“At this moment in time, learning that you’re not going to be ready until late November is massively upsetting.
“But there is another six months left of the season and a lot of football to be played.”
This article was originally posted here