Two photographs are captured within a single picture frame that hangs on a wall inside Gary Caldwell’s office at Exeter City.

They were taken four days apart in 2013. The top one shows Caldwell is on his knees among dejected Wigan teammates in the aftermath of a defeat they all feared would consign them to relegation.

In the other, those same players are euphoric. They are singing and bouncing on the Wembley turf in celebration, and Caldwell is reaching out to touch the FA Cup.

It might get a mention on Tuesday as his team, winless in League One since Boxing Day, try to topple Nottingham Forest, bang in form and 57 places up the pyramid, dreaming of the Champions League after seven goals against Brighton on their last outing.

Caldwell knows strange things happen when the stars align in the FA Cup and he knew before Devon neighbours Plymouth stunned Liverpool.

Gary Caldwell poses under two photographs in his office – one of Wigan’s imminent relegation, the other of their FA Cup triumph – which remind him of the rollercoaster nature of football

Exeter celebrate beating Championship side Oxford United to reach the FA Cup fourth round

Wigan club-captain Gary Caldwell lifts the FA Cup in 2013 alongside Emmerson Boyce

Maybe Nuno Espirito Santo will make 11 changes as he did in the third round against Luton. Maybe Forest are distracted by their bid for Champions League football. Maybe Exeter can seize the moment.

‘Since the draw came out, we hoped they’d keep on winning,’ says Caldwell. ‘See the money in the Champions League as their main priority. We know their quality. They have an outstanding manager and any team they put out will be high calibre. It’s a huge challenge but one we should embrace.

‘Everyone has a role, big or small, and if everyone plays that role to the very best, I believe you can be successful. No matter who you are. I saw that at Wigan.

‘Nobody expected us to the win the FA Cup but everyone bought into what we were doing. Roberto Martinez was a brilliant manager, who knew how to find a tactical advantage to beat the best teams. We took that into the FA Cup and I try to take that into my management.’

Wigan’s triumph against Manchester City 12 years ago is perhaps the last time the FA Cup delivered true underdog winners and Caldwell was the club captain.

With painkilling injections in both hips, he played in the first of those games in the frame on his wall, at home against Swansea when Wigan led twice and lost 3-2.

‘I had a fair idea I wasn’t going to play at Wembley,’ says Caldwell. ‘I missed a lot of games second half of that season and hadn’t played in the FA Cup games. Roberto knew I was struggling, although he probably didn’t know how much.

‘I had bad hips from my mid-to-late 20s. I’d already had double surgery a few years before and that season the left one started to give me a lot of pain. The doctor was injecting me to train and play which, in hindsight probably wasn’t the best idea.’

Gary Caldwell talks through the highs and lows of his career with Mail Sport’s Matt Barlow

Ben Watson (right) wheels away in delight at scoring the winning goal for Wigan in the FA Cup final victory over Manchester City in 2013, one of the competition’s biggest ever shocks

Wigan keepers Joel Robles (left) and Ali Al-Habsi come to terms with relegation from the Premier League just four days after the highs of the club’s Cup triumph at Wembley Stadium

Caldwell underwent surgery at the end of the season and would make only five more appearances. By the age of 32 he had played his last game. By 35, he had two hip replacements.

‘It was my job at the time,’ says the Scot, now 42. ‘I had to play, but I was in a lot of pain.’

Although an unused substitute in the Cup Final, he was urged by assistant boss Graeme Jones, now coaching at Newcastle, to lead his team up the Wembley steps and lift the trophy with Emerson Boyce, captain on the day.

‘My John Terry moment,’ says Caldwell. Chelsea captain had changed into his kit the previous year to lift the Champions League trophy when suspended and unable to play in the final.

‘I was unsure what to do and Graeme came up and said, “get yourself up there with Boycey, you know, you’ve done a lot for this club” That was really good of him. It’s easy in a euphoric moment to forget others.

‘That’s when I took my tracksuit top off. I thought if I’m going up the front I might as well make the picture look better. To walk up those steps with your teammates, people you’ve been with through good and bad times and to have that moment was amazing.’

Celebrations were hardly excessive. They travelled home on the team bus and Caldwell hosted the families of Shaun Mahoney and match-winner Ben Watson for a barbecue the next day, but they were on a train heading back to London on Monday, where defeat at Arsenal confirmed relegation on Tuesday.

Wigan have not been back in the Premier League since. Changes in ownership and financial crises pushed them to the brink of liquidation. Now, they reside with Exeter in the lower reaches of the third tier. Yet few would trade that day at Wembley for staying up.

Caldwell is sure no one had Wigan would substitute their FA Cup victory for having stayed up

Former Wigan manager Roberto Martinez, now Portugal boss, was a big influence on Caldwell

Gary Caldwell is a picture of frustration after missing a penalty in the 2014 FA Cup semi-final

‘That will never ever be forgotten,’ says Caldwell. ‘It obviously came at a huge cost in terms of relegation, money, the difficulties since then, but I wouldn’t swap it. I don’t think the town would swap it or the people there on the day to experience that high.

‘It is the reason you play the game. You don’t play the game just to stay in the Premier League. You play the game to win something and to create special memories. We managed to do that. Little old Wigan went and won the FA Cup in 2013.’

When they reached the semis a year later with Caldwell coming on as a sub against Arsenal at Wembley for his first appearance since hip surgery the previous summer. He came on at 1-1, helped them survive an onslaught in extra-time but missed a penalty as Wigan, then under Uwe Rosler, lost the shootout.

‘Uwe said, ‘Right, who wants to take a penalty’,’ recalls Caldwell. ‘I put my hand up along with three other people and I’m thinking, “well, we need one more lads”.

‘Jack Collison was the fifth. I missed one and he missed the other and we went out. That was an incredible defence of the FA Cup and with Hull in the final we left thinking, potentially we could have won it again.’

Exeter have made history this year, beating Oxford of the Championship to reach the fourth round for the first time since 1981, when as a third-tier team they toppled Leicester and Newcastle before losing to Tottenham in the last eight.

‘You end up on a run, you don’t plan for it,’ says Caldwell. ‘One club every year creates upsets and there’s a bit of a story. As I said to the players before Barnet in the first round, why can’t that be us?’

To reach the fifth round again would be incredible for a club wholly fan-owned since they were taken the brink of liquidation by rotten ownership early in this century and rebuilt with the windfall from two FA Cup ties against Manchester United in 2005.

After a goalless draw at Old Trafford, Wayne Rooney and Cristiano Ronaldo scored to settle a replay at St James Park. The tie has special place in the heart of the club which explains the angry reaction when replays were scrapped this season.

‘It has taken something away from the competition,’ says Caldwell. ‘For all smaller clubs down the football pyramid it is a disappointment, especially when they see the bigger clubs go off on friendlies all over the world to make even more money. I think the Premier League gives them enough.

‘This would be a great example, because if we could draw this game we’d have an away tie at the City Ground and generate more money for the football club.

‘It’s a shame because the competition over the years will have saved loads of smaller clubs that are really important to the people who follow them and the communities they are in.

‘We need to look at for the wider picture of football in England and not just the Premier League and the bigger clubs getting the ability to generate more and more money.’

A debate to be continued on another day perhaps. On Tuesday, his Exeter take on Forest aware they must win to earn another money-spinning FA Cup tie this season.