Making your senior debut in the Premier League at Stamford Bridge, after years of hard work and sacrifice, should be one of the career highlights for any footballer. With your family watching on proudly from the stands and your manager, a childhood idol, demonstrating his unflinching faith in your ability to handle the big stage, that moment is the realisation of a lifelong dream.

However, for 18-year-old Billy Gilmour, there were mixed emotions as he sat in the dressing room on that Saturday evening at the end of August. The young Scottish midfielder had been sent on with six minutes remaining of a tight league encounter with newly-promoted Sheffield United, the Blues leading 2-1 thanks to a first-half brace from Tammy Abraham.

Frank Lampard’s side had recorded their first win of the campaign a week previously, away at Norwich City, and were aiming to sample that sweet taste of victory for the first time under the new boss at the Bridge. The Blades had not been fully blunted though and a goal 45 seconds after the restart had halved our advantage and restored their belief.

With the pressure building and the hosts losing their grip in the midfield battleground, Gilmour was sent on to help his team-mates get over the line. Given the precarious nature of the contest, it was another sign of Lampard’s faith in young players, although even at the time the decision drew questioning glances.

Would Andreas Christensen not be a better option as an additional defensive shield in front of the back four, or the height of Marcos Alonso an effective weapon as Chris Wilder’s side drew closer to our 18-yard box?

Lampard would later admit, months on as Gilmour was the recipient of widespread praise for performances against Liverpool in the FA Cup and Everton in the Premier League, that he was directly questioned by some on why he had trusted such a young, untested player at such an important moment.

‘I remember when he first came in against Sheffield United, we drew the game and people questioned this kid who looks like a 15-year-old,’ recalled Lampard. ‘I remember someone individually saying that to me.’

The Blues saw two points slip away with minutes remaining when Kurt Zouma turned a teasing cross into his own net to make it 2-2. The narrative had been set and pundits questioned whether Lampard was too trusting of the youngsters. Gilmour felt the pain of defeat as much as anybody, admitting it spoiled the landmark of his debut, though a message from his boss later that night provided a timely boost.

‘When the game finished I remember walking back to the changing room and I was raging,’ the teenager tells the official Chelsea website. ‘I was gutted at myself just because of the score.

‘The gaffer texted me later saying "these are the moments I want you to remember. When you’re training hard, that’s what you need to bring into the games when people aren’t playing well. You need to take the good and the bad together."

‘It was a tough game. Sheffield United worked really hard. I was obviously happy that I’d made my debut but mostly gutted. My family came down to watch and they kept telling me to cheer up. They wanted to take pictures afterwards but I wasn’t really smiling because I was in a bad mood!’

The references to his lack of physical stature, however, did not affect him. At 5ft 7in, Gilmour might be diminutive in size but he makes up for that with a hard-working, hassling nature alongside the ability to think and play quicker than most. Besides, he’s been playing against bigger and stronger opponents throughout his teenage years and knows how to adapt.

‘Going through the years, even with Jody Morris and Joe Edwards in the Academy here at Chelsea, we’ve talked about it when we’ve played against bigger teams,’ he explains.

‘I just have to be one step ahead, be quicker with the ball at my feet because technically I’d say I was a good player but physically is the side I need to work on. I know I’m not going to be the biggest or strongest player but I have to make sure I’m always scanning, trying to find space and thinking what’s going to be the next best pass.

‘Training with the best players every day helps that. It’s very competitive and when you’re up against the big players you have to treat it like a game because you’re going to come up against players like that in the Premier League.’

After travelling with Lampard and the senior team to Dublin for pre-season in July, Gilmour has trained with the group fairly regularly ever since, while playing the majority of his match football for our table-topping, unbeaten development squad in Premier League 2.

He believes the mix has been ideal for his development this season and justifies the decision not to go out on loan either in the summer or January. The advice and instruction of Lampard was key to that as well.

‘One of the best things that’s happened this season has been training with the first team because it means I have to keep my standards high and train hard every day,’ he continues. ‘Then when I go down to my own age group with the development squad, I’m continuing to keep the standards high and take that into games - we’re still unbeaten, top of the league and we’ve done so well.

‘I felt I did well in pre-season but I did think when we came back that I’d be going on loan. The gaffer and Jody spoke to me and said they thought it was best for me to stay, play games with the Under-23s and train with the first team a lot more. I was happy with that, especially the chance to get more opportunities to train with the first team and express myself and show them what I’m about.

‘At Christmas time, I was thinking I might go out on loan for the rest of the season but got told to stay again and got moved into the first team building. That’s when I started to kick on from there by playing games consecutively and playing well so it’s worked out really well for me. All I can do is thank the manager for trusting in me.’

The pause to proceedings in football came at an unfortunate time for the Scotland Under-21 international, who had just played in back-to-back men’s games for the first time in his career. Not only that, he had been awarded the man of the match honour in both games and received widespread praise for his calm, controlling presence in midfield in victories over both Merseyside opponents.

‘It was a bit frustrating to stop when we did but when something like this happens it’s better to be safe and it was the best decision made,’ he explains. ‘Hopefully when we’re back, I can hit the ground running again and pick up where I left off.

‘When we played Liverpool, I was just excited to play and start my first game. It was something that I’d been training and working hard for. To then play against Everton a few days later, I was thinking "this is good, I’m playing well." They were two different games, obviously one in the FA Cup and one in the Premier League, but I enjoyed them and the team won so that was a good thing.’

Football is a fickle business and Gilmour is well aware of that. He remembers the doubts from August just as much as the current admiration coming his way. He also remembers Lampard’s words in the aftermath of the Sheffield United game, to keep working and take the good with the bad.

‘It’s great when you hear the pundits and ex-players speaking about you and saying nice things but at the same time you have to remember that football is like a rollercoaster,’ he says.

‘You can be playing really well but as soon as you have a bad game then stuff happens. I just need to keep doing what I’m doing, keep my head down and focus.’

The grounded Gilmour was the name on everybody’s lips before football began its long pause and he is determined to keep it that way.

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