SCOTT Brown has been here many times before in his Celtic career. Written off by his detractors. Dismissed as a spent force by those who wish him ill. Tipped to struggle as his powers diminish.

But the Celtic captain, who has revealed he will sign a new contract at the Parkhead club in what is his testimonial year, is taking the same attitude to the snipers, of whom there has never been any shortage, as he has always done.

It would be impossible to have survived for as long as he has in Paradise without being able to withstand the flak. The barbs which are aimed in his direction bounce off the midfielder like rival players trying to dispossess him. If anything, they provoke a positive reaction.

Read more: Celtic and Scotland skipper Scott Brown to play on for both club and country 

The Herald: Celtic captain Scott Brown in the Parkhead club's new away strip at their pre-season training base.

“It is only a matter of time before somebody wants to kill you off,” said Brown from the Czech Republic, where Celtic have come to play their third pre-season friendly against Slavia Prague this evening, yesterday afternoon. “But it has been that way in my career for the last 15 years. People have always done that, people can’t wait to knock you down.

“I don’t give a flying f***. People can think whatever they want of me. I do my job for Scotland and I do my job for Celtic. I work as hard as I possibly can. I do whatever I need to do in training and outside of training to be the best I can be.

“You need to have a thick skin to do this. The abuse I get? That’s life. People can write on Twitter or Instagram or whatever. It doesn’t really bother me. I enjoy seeing the wee comments like ‘Scotty, you’re s****.’ I think: ‘I know mate - but I’m still playing and I’m 32!’ I’m just here to prove everyone wrong – even the sports science guys here.”

He has certainly done that in the last 12 months. This time last year the focus on Brown was intense and the pressure on him to perform considerable.

He had, despite helping Celtic to win their fifth consecutive Scottish title, been a shadow of the player he once was. He had suffered from a series of niggling injuries. He looked unfit and his form was often poor. At 31, even many of his admirers thought he may be in decline.

Read more: Celtic and Scotland skipper Scott Brown to play on for both club and country 

But a complete break from the game last summer, coupled with the arrival of Brendan Rodgers as manager, transformed him. He was back to his very best both domestically, where his side went undefeated and won the treble, and in Europe, where his team qualified for the Champions League group stages for the first time in three years.

Retiring from international football last August after winning his 50th cap – a decision he went back on after just two months – undoubtedly helped to replenish his energy levels.

So, isn’t the fact that he is back playing for both club and country going to take an inevitable toll on his body once again? He is confident it won’t. He revealed he had the complete faith of both Rodgers at Celtic and his mentor and friend Gordon Strachan with Scotland too.

“I just need to maintain my levels of fitness,” he said. “If I know I can play at that level I will continue doing it as long as I can. If I can’t then I will know it is time for me to go. As soon as I can’t chase the lads at training I will know I am letting them down. It won’t be a decision that anyone else will make.

“For me, it is in the runs more than anything. When we are doing sprints and I am closing people down and I can’t keep up I think that is when you know your legs are going and your time is slowing fading away.”

Brown had less than a fortnight off after the Russia 2018 qualifier against England at Hampden at the end of last month. But he feels the impressive levels of strength and fitness which both he and his team mates have attained under Rodgers is helping him to cope better with the demands which are placed on him both physically and mentally.

Read more: Celtic and Scotland skipper Scott Brown to play on for both club and country 

“I am actually alright,” he said. “I thought with the 10 or 12 days off I would have come back struggling and feeling like I’ve not been away. But, no, it has no bother whatsoever. I caught right up right away. Everybody else has looked after their body and has stayed sharp. We are probably as fit as we ever have been at this stage due to us not having that long time off.”

“I think for me the issue was with groins and around the pubic area. I need to protect myself from that. But I have come back in and am not feeling anything whatsoever. I am back doing what I normally do. I have the same stats as I did at the end of last season. You catch up really quickly.

“When the gaffer came in he was keen on making sure everyone looked after their body, on making sure you are going in and getting rubs, doing what you need to do to make sure you are fit for the next day’s training so you can push your numbers higher than they have ever been before.

Strachan, who famously played on until he was in his forties, has been struck by the change in the player. “I was speaking to Gordon when we were away with Scotland and he was talking about how much fitter I looked compared to the season before when we met up just before I retired. He told me ‘if you keep going at that pace I don’t see why you can’t push for three of four more years’. As soon as you can’t chase the young ones that is game, set and match.”