MIKAEL LUSTIG has gone from just about struggling through matches to winding up Neymar on Champions League nights.

Celtic’s Swedish right-back used to feel injured all the time and the very thought of facing any Brazilian superstar was fanciful given how unfit he was.

Now he’s in the form of his life and well the way to having the best season of his career. It's a turnaround he really needed.

Lustig said: “A couple of years ago it wasn’t much fun. I always felt as if I’d pull a groin or a hamstring or something. But I decided to go back to the way I was when I was at Rosenborg when I was never injured.

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“I get little knocks on my ankle and knee but these can happen to anyone. Over the past year I’ve played a lot of games and I feel really, really strong. The routine I returned to is more to do with what I do after training – work in the gym and the like.

“It’s nothing big on my diet – I’ve always been good about what i put in my stomach. It’s all to do with fitness and gym work to keep me at my best.”

Lustig’s return to health and form was epitomised by his refusal to be intimidated by Neymar. The two players seemed to rub each other up the wrong way in last week's game in Glasgow.

“There weren’t any heavy tackles – it was just two guys who moaned at each other,” said the Celtic man. “It was nothing special.

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“He’s better than me so to try and compete you try to stay close and sometimes you need to pull some tricks and get into his head. It was job done when he reacted but then I didn’t show my experience when I chased after him and got a yellow as well!"

Stuart Armstrong is another whose future at Celtic a year ago was far from certain. He was out of the team and when he did play was out of position.

The midfielder this season has become a big part of what Brendan Rodgers is trying to do.

“It’s a big thing for me to be involved and feel at the heart of it,” said Armstrong. “Even at the start of the season, I was out. I’ve had a good run in the team now in a central position, which I love, and I really feel part of this team.

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“It’s nice to be a part of things when we are winning and doing well. It’s so enjoyable.

“It was great to win a cup so early in the season. It puts a marker down and now we can focus on being relentless in the league and we have our ambitions in the Scottish Cup as well.

“Losing the League Cup Final would not have ruined all of the good work as we’ve achieved good things in the Premiership and we are undefeated in that.”