Mulgrew hoping to end frustrating season on a high

That was followed, after Legia's subsequent expulsion for fielding an ineligible player, with the acute disappointment of defeat to NK Maribor and failure to qualify for the lucrative group stages of Europe's elite club competition the next month.

Less than a fortnight later, Mulgrew was ordered off for a second bookable offence playing for Scotland in front of 60,000 fans in a 2-1 defeat to newly-crowned World Cup winners Germany in Dortmund.

Then at the start of December, just as the Scottish champions were beginning to click under their new Norwegian manager Ronny Deila, he sustained a knee injury that was supposed to sideline him for six weeks.

Those six weeks turned into just shy of six months. His return to the Celtic side as a second-half substitute in the SPFL Championship match with St Johnstone at McDiarmid Park on Friday night brought to an end what has been an unsettling period.

"It is the first time I have had an injury where some days there is no improvement," he said. "Any muscle injury I have ever had, it keeps getting better and then, all of a sudden, it is away. But it wasn't like that with this. I didn't know if it was getting better.

"It was my hamstring tendon. Tendons don't have a lot of blood supply to them, so they tell me. They don't heal as quickly. They can be a bit more complicated. There are different ways to treat them and it is just finding the right way that responded well to my body."

During that prolonged process, Mulgrew had to look on as Celtic played Inter Milan in the last 32 of the Europa League, defeated Rangers in the first Old Firm game in three years en route to lifting the League Cup and claimed their fourth consecutive Scottish title.

As a boyhood supporter as well as a squad member, he was delighted at Celtic's success. However, he wouldn't be human if his own inability to contribute in some capacity hadn't rankled.

"Of course you are supporting the boys, wanting them to do as best as they can," he said. "But you obviously want to be involved, want to be out there helping them. It was frustrating at times when things weren't going so well, which hasn't been often. Unfortunately it wasn't my time."

Mulgrew, 29, has been afforded limited opportunities to show his new manager what he can contribute to the side. Still, he was appreciative of the interest Deila took in his rehabilitation. "The manager is brilliant like that," he said. "He had a lot to focus on with the team. But he did find time to speak to me and was very positive so that helped."

In Mulgrew's extended absence from the Celtic first team, Nir Bitton established himself in central midfield alongside club captain Scott Brown. The former PFA Scotland, SFWA and SPL Player of the Year is one of Bitton's many admirers. He admits, though, his thoughts did stray to what the implications of the Israeli inter- nationalist's breakthrough would be for him as he struggled to regain fitness.

"I have been impressed with Nir," he said. "He is still young, but it's no surprise to me that he has done well. I have seen what he could do in training. But we all like the challenge of fighting for places because it brings out the best in us.

"Your mind thinks: 'Will I get my place back?'. But that is part of being at a club like Celtic. Even when you're fit, you know there are people who can come in and do well for the team. But it is worse when you're injured."

Scotland, too, have not exactly mourned the temporary loss of Mulgrew. James Morrison slotted into his berth for the Euro 2016 qualifiers against Georgia, Poland and Gibraltar and helped the national side pick up seven points out of a possible nine. They are now level on points with Germany in second spot in Group D.

It has been a demoralising time. When Mulgrew reveals a visit to the dentist lifted his spirits, you realise just how demoralising. Yet, a chance encounter with Gordon Strachan at a routine check-up, had exactly that effect.

"I bumped into him at the dentist," he said. "He came out as I was going in. We had a chat. I told him my situation and everything was very positive. He was happy with that."

As, for that matter, was Mulgrew. The prospect of representing Scotland against the Republic of Ireland in a Euro 2016 qualifier in the Aviva Stadium in Dublin next month is an appealing one. Strachan names his squad for the games against Qatar and the Republic of Ireland tomorrow. Being included would end what has been a wretched campaign on a huge high.

Asked if he could be involved against the Republic after such a long spell on the sidelines, Mulgrew said: "I'm desperate to. That's why I'm hoping I can be involved in the last couple of games with Celtic, to push myself forward for that.

"I'm delighted to be back in the Celtic squad and hopefully he [Strachan] can pick me for the Scotland squad. I think I will be mentally fresher than a lot of players who are kind of winding down."

Mulgrew believes the friendly international against Qatar at Easter Road on June 5, will give him the opportunity to convince Strachan he merits inclusion in his side eight days later.

"That would be a good place to show I'm fit and ready," he said. "So hopefully I get the call-up and I can get more match sharpness."

Incredibly, the former Aberdeen and Wolves man has managed to squeeze a career highlight into an otherwise demoralising campaign. In November, he produced arguably his best performance for his country in the 1-0 win over Ireland at Celtic Park, being named man of the match.

"Scott [Brown] and I did well that night, but it was a good team performance," said Mulgrew, who has 16 caps. "It was a battle and we enjoyed it obviously because we won. This game is massive, but we aren't thinking everything hinges on it. We want to win, of course, but there is still a long way to go."

If he does take to the field in Dublin, Charlie Mulgrew will have completed quite a journey of his own to get there.