Griffiths retweeted a supportive message from a Celtic fan which featured a video of him lifting silverware and scoring goals for club and country, and wrote: "Not long before I'm back doing all this!"

The 28-year-old announced on Sunday that he was off work "due to my mental health state" and "not gambling, not drugs, or any other issue that has been written about me since December".

The Scotland international spoke out after photographs of him attending a racecourse meeting appeared on social media and on newspaper front pages.

Celtic manager Brendan Rodgers later reminded the former Wolves man to take responsibility for dealing with his issues.

Rodgers told several newspapers earlier this week: "It's very important that he understands why he is off and why he has been given the time off. Why he has to maximise that time in terms of getting better.

"That's about getting specialist help and lying low and focusing on the simple things in your life that will allow you to be better."

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