Over a year has passed since a crestfallen Celtic huddled together at the centre of Hampden, their treble dream in tatters.

Having it dramatically wrestled from their grasp in last season’s Scottish Cup semi-final still stings a group which has since swept all before them domestically. That it came against Rangers only deepens that pain.

But as the teams prepare to meet again, on the same stage and at the same venue, there’s a feeling it will take something truly special to deny Celtic this time around. The League Cup is nestled away in the trophy cabinet already, and a second consecutive Premiership title is all but in the bag amid a staggeringly consistent run comprised of just a single defeat in 45 domestic outings.

But such is the relentless demand for success at Parkhead, Ange Postecoglou will not allow his players to rest until they complete that coveted clean sweep. The 57-year-old is not one for dwelling too much on the past, but believes his players are stronger for that setback in April 2022.

“You don’t bottle it up for 12 months,” Postecoglou said. “You use it for the next week and the week after that. At the time that group of players were really bonding together. 

“They’d already been through some tough times earlier in the year but we’d got ahead in the league and had really turned things around. Part of the progression and I guess the development of the group is how you react to times that are not as successful. 

“I thought the group really responded after that game and made sure they finished the season strongly – and as champions.  Those kind of things you use at that moment.  You don’t keep it for the next time you are in that position because ultimately you may never be in that position again. You use it at that moment and we did use it really well as a group. 

“We learned from it. The boys took that disappointment on board and have used that ever since to make sure we take every opportunity we can.”

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Afterwards, it was noted how Rangers appeared to come on stronger in extra-time, despite having played 120 minutes in the Europa League against Braga just three days prior. Scott Arfield had cancelled out Greg Taylor’s opener in normal time, before a driving run from Calvin Bassey forced a Carl Starfelt own-goal in the 114th minute.

But Postecoglou outright rejected the notion that inferior fitness cost Celtic on the day.

“No. I don’t know how you answer that,” he said. “We must have been fairly fit because we won the championship. I don’t think that a team that’s unfit can win a title. 

“Look, on the day it was a tight game. To Rangers’ credit, they got the job done in extra-time.  They were a strong team last year. It was a team that made the final of the Europa League. 

“It was a tough game and a tough contest. They got their nose ahead in extra-time and ended up getting the job done.”

Callum McGregor, meanwhile, still remembers the feeling when he gathered his team-mates together for a painful debrief as Rangers lapped up their success at the other end that day. The Celtic captain has not suffered through too many disappointments during a trophy-laden career, but even he admits the setbacks linger in the mind well beyond the celebrations.

“When you have disappointments like that in football, it sits with you a lot longer than the positive times” the 29-year-old said. “You remember them for longer, it hurts for longer. When you get a chance to rectify it, you have to do everything in your power to do that and right the wrong.

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“The last time we went to Hampden was the League Cup Final and we felt like we owed them one from the semi-final last year. We managed to make that a positive experience.

“Again, this group will still be feeling the hurt of what happened 12 months ago, so it’s important we carry that emotion. You don’t let it cloud your emotion in terms of what you see on the pitch, but it can fuel you to go on and achieve better things.

“We’ve had a great 12 months since then, and the next progression to that is a big game at the weekend. We have to do everything we can to make that a positive experience as well.

“No, we haven’t spoken about it at all, to be honest. It was 12 months ago and we’ve had a really positive year.

“We haven’t discussed it because it will probably still hurt some of the players. That’s a personal thing, an internal thing.

“With the group, you try and be positive, and we’ve had a really positive 12 months. The big task for us is to try and turn up and play our football in a big semi-final, and hopefully progress to the final.”

McGregor demanded a reaction to Sunday’s 1-1 Premiership draw with Motherwell, an unusually lethargic display, even if Rangers’ defeat at Aberdeen ensured their lead at the top stretched to 13 points. In a slightly ominous sign for Michael Beale’s side, only once under Postecoglou’s leadership have Celtic failed to respond to a domestic setback with victory in their next game.

“That’s the nature of trying to create a positive from a not so positive result, getting a reaction from it,” McGregor said. “To win the next game is almost non-negotiable, in terms of the reaction side of things, the fixtures will always play a part in that as well. Ultimately, we’re looking for a positive reaction to what didn’t go so well in the previous game and implement that into the week’s training.

“Hopefully, that gives everybody clarity moving forward into the following game. That’s a nice stat in terms of the mentality of the group and the bouncebackability that we seem to have.”

As ever with these fixtures, there is so much riding on Sunday’s 90 minutes. Victory would propel either side as overwhelming favourites into a final against either Falkirk or Inverness Caledonian Thistle.

For Celtic, that brings a fifth treble in six years careering into view. But McGregor knows that this final chance to win a trophy could see them face a Rangers side prepared to throw the kitchen sink and more at them.

“They’ll want to win the game,” he said. “It’s no different to any other derby game where there’s a lot on the line. Of course, there’s pride for the supporters from both sets of players.

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“You’re always playing for something in these fixtures and, in terms of the cup, if they progress they’ll be in the final and if we progress we’ll be in the final. There’s a lot riding on the game, but you can’t think too much about that.

“You have to prepare for the game. Rangers have tried probably three or four different ways of trying to set up and stop us playing in the three or four games we’ve had this season.

“I’d imagine they’ll pick one of them, or a combination, to try and stop the game and stop us being positive. It’s then up to us to turn that on its head and find a way to play in the game and be positive.

“There’s interesting little battles, tactical battles. In the main, you have to turn up, be prepared and as always in a cup game, play well to go through.”