The dread came from the identity of the man it was that wrote the post to accompany a picture of himself running in blazing sun.
And the Rovers legend has admitted to the Free Press that it could very well be his final year as a player before hanging up his proverbial well-worn boots for good.
"I have thought that, I'm not going to lie," the 38-year-old told the Free Press.
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"When I do come away from football, it's not until then that you realise how intense it is.
"For ten months of the year I give everything. There's a lot of sacrifice in terms of family.
"I'm not complaining but when you do step out of it for six or seven weeks it's actually nice to do normal things and just get on with your life.
"You don't have to worry about what you eat, worry about your recovery, or worry about this that and the other.
"As a player you take it for granted when you're younger because you haven't got other responsibilities.
"But I've got three kids now and I travel up and down the motorway every day and there is only so long that I can do that.
"I've definitely had time to think over the summer.
"I don't want to speak too soon and I'll just see how it goes this season but I'm definitely getting closer, put it that way."
Coppinger has consistently said he has avoided adding anything to his schedule which could distract from his playing career.
It is why that while he does hope to enter coaching in the future, he has taken no major steps at working towards that so far.
Anyone looking for further hints he may be approaching the end of his time on the pitch would have noticed him taking on a few other ventures over the summer.
Coppinger was announced as a new ambassador for hometown club Guisborough Town.
And he became the franchisee for Kixx, an organisation that delivers football classes and coaching for children from toddler age upwards.
Considering his future as a player led to Coppinger becoming more open to new avenues for his life.
And he says these two ventures fit perfectly with his outlook on the game.
"I think for me personally, I've thought about it for the last three or four years and I didn't want to just dip in to other things too soon," he said.
"But I've been pondering what I want to do and how I want to do it.
"Kixx came for me at the right time. I love what it's about, I love it's values and what it stands for.
"Football for me is about learning, growing and understanding. It's not just about winning, it's about all the other things that come with it.
"If you can get that through to kids when they're younger you've got a better chance of them learning and developing and enjoying football rather than resenting it when they get to a certain age.
"It's a fantastic way of doing it. Kixx have got a unique selling point in that respect.
"Guisborough Town is the same.
"I was brought up in the town and sometimes when you come from a small town you can almost limit what you can achieve. It's not just in football but in life as well.
"It comes down to how you're conditioned and coached and who is teaching you.
"If I can help in any way shape or form with the younger lads growing up and making them believe they can achieve anything, that is something I want to get involved in and I'm passionate about."
Though admitting the end is near, Coppinger says the decision is not final and for now, he is looking forward to the campaign ahead - his 16th as a Rovers player.
"It's over before you know it and it will definitely be over in the next few years for me," he said.
"I enjoyed last season with the group that I worked with.
"I'm looking forward to this season and doing the same.
"It's year by year and month by month for me.
"We'll see how it goes this season and see if it is the last one."