Now the defender hopes he can play a part in developing Partick Thistle's inexperienced stars as the Jags bid to beat the drop this term.
Mair brought the curtain down on his Buddies career earlier this month to join Alan Archibald's side and has made an immediate impact at the heart of the Firhill rearguard alongside Conrad Balatoni.
Jordan McMillan is the only other defender on the Jags' books who has top-flight know-how and Mair is eager to pass on his knowledge to his young team-mates.
He said: "The manager said to me to come in, use your experience and talk to the kids. I couldn't believe how young they were.
"They are a good bunch of kids so I am talking them through the game and letting them go and enjoy it.
"They are young and they need an old head like myself to look after them. Ability-wise they have nothing to fear in this league at all.
"I have done it since I started doing my coaching badges. I have added that to my game.
"When I left St Mirren, Thomas Reilly, Jason Naismith and John McGinn texted me to say thanks for everything you have done for me over the last couple of years, so that meant a lot.
"I have continued that here and hopefully I can help them here as well."
Mair may be one of the most experienced stoppers in the Premiership, but he was often overlooked by Buddies boss Danny Lennon and struggled for first-team football in the opening months of the campaign.
He made only a handful of appearances for the Saints before heading for the Paisley exit door, and the former Dundee United and Aberdeen star admits he is loving life at Firhill.
He said: "I have been here a week and played as many games in that week as I did in the whole season at St Mirren.
"I played three games in a week and it was brilliant to be thrown in.
"You are going to bed at night thinking 'what striker am I playing tomorrow?' and your head is on the game.
"For the last eight or nine months, my head has been elsewhere, if I am being honest. I was training with the kids and it was quite tough.
"To be back in now and focused on a game on a Saturday is what it is all about and I am really enjoying it.
"I am 33 now so I need to be playing. I have got more games behind me than I have in front of me now: I want to use the next two or three years to play as many matches as possible."
After claiming a point on his Paisley return last weekend as Archibald's side drew 0-0 with their relegation rivals, Mair will bid for his first win in red and yellow when Dundee United visit Firhill this afternoon.
The Jags have yet to triumph in a top-flight clash on home soil this season and are eleventh in the standings after a frustrating recent run.
Mair said: "I think we have been unfortunate not to win games. In the last two, we should have beaten Kilmarnock and got more from the St Johnstone game. Hopefully with a bit of the rub of the green we can put that right."