As a single-minded 36-year-old sportsman “just trying to keep going” at the highest level, James Milner has little time for reminiscing. With a momentous milestone on the horizon, however, he has no alternative. On Thursday the Liverpool midfielder will celebrate the 20th anniversary of his Premier League debut. Perhaps with a yoga session at home after training, though certainly not with an alcoholic drink.

It was at Upton Park on 10 November 2002 where Terry Venables launched the top-flight career of a 16-year-old Milner, bringing him on as an 84th-minute substitute for Jason Wilcox in Leeds’ 4-3 win over West Ham. For perspective, Wilcox is 51 and academy director at Manchester City. Nigel Martyn was on the Leeds bench and was the same age as Milner is now. The veteran goalkeeper took the Premier League’s then second-youngest debutant aside and urged him to savour every moment of a career that would flash by “like lightning”. Three Premier League, one Champions League, two FA Cup and two League Cup winners’ medals later, the conversation still resonates.

“I remember Nige saying that to me and I was like: ‘Leave it out Nige, I’m only 16.’ Then bam! Twenty years later. He was bang on,” says Milner. “You never know what is going to happen. Look at the journey I’ve had and the amount of manager changes I’ve had.

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“In the second season, when Peter Reid started putting players on ahead of me, I went on loan to Swindon for a month because I wasn’t going to be involved. When I came back, I played every game. It’s little things. I went to Newcastle and Sir Bobby Robson got sacked within a couple of months. A new manager [Graeme Souness] comes in. He wanted more experienced players so, again, I go out on loan to Villa. When you think about it, there are so many stumbling blocks. It’s not like every manager has said: ‘I’m having him as a player.’ You have to keep proving yourself again and again and you know people are doubting you.”

Milner is on the brink of another milestone, a 600th Premier League appearance. Only three players have reached that tally in the Premier League era – Gareth Barry (652), Ryan Giggs (632) and Frank Lampard (609) – although the midfielder is unable to join that select club at Tottenham on Sunday due to concussion protocols stemming from the 2-0 win against Napoli on Tuesday.

Toughest opponent “Messi. Unbelievable.”

Best goal “I’d have to pick three. My first for Leeds at Elland Road. Newcastle v Man United at St James’ Park. Gary Neville had just walloped me into the air. I went off injured, came back on, cut inside him and smashed it in the top bin. And Villa at Sunderland away, a 30-yarder.”

Hero “Alan Smith at Leeds. He was a local lad coming through the academy. He did what we all wanted to do, scoring with his first touch at a big ground - Anfield, and in front of the Kop.”

Best performance “Has to be the 4-0 versus Barcelona.”

 Biggest influence “It feels unfair to name one because of the amount of people I have been lucky enough to work with, players and managers. But my parents and my wife are the biggest reason I am still playing now.”

Best advice “Work hard. Want it. My dad used to say that whatever I practised on my right foot I had to do with my left. If I did five shots with my right I would do the same with my left. That has helped me play in 50 positions, I suppose.”

When were you at your peak? “My best individual seasons were one at Villa, the year before I moved to City, when I scored a fair few goals and got into the England squad. I played every game in the middle. City signed me on the back of that. And then with Liverpool we had one year in the Europa League and the next in the Champions League and I had a lot of assists.”

The highlight? “To pick one is tough because there is every time you win a trophy and I’ve been fortunate enough to win some big ones. Making my debut at Leeds, scoring my first goal for Leeds and then doing it again at Elland Road a few days later, they are massive highlights.”

Biggest regret? “Two stick out. Being relegated with Leeds and not being able to celebrate the league title with Liverpool, given how long they had wanted it, being able to achieve it and it being behind closed doors. That was a big regret and a big shame.”

The veteran attributes his longevity to good luck with injuries and a driven mentality: “That stubbornness I have to always want to prove myself, to always want to be the best guy in training or want to show up the young lads in pre-season,” as he describes it. But it is fortune and determination of his own making. A teetotal lifestyle is not unusual for a top-flight professional in 2022 but it was different when Milner was progressing through the ranks at Leeds. The steely determination that drives Milner, evident in his recent match-winning challenge on West Ham’s Tomas Soucek and which Jürgen Klopp considers a priceless influence on the squad, was present from the outset.

“I lost count of the amount of times people said: ‘Oh, just have one,’ or ‘Can I be there when you have your first drink?’ They would probably have regretted being there if it had happened; I could have turned pretty ruthless. You don’t know, I could have been a hugger and a kisser as well. You are just learning at that age and thinking: ‘What can I do to be the best?’

“Alcohol is not the best thing for you? Right, I won’t do that. After training I’d practise corners and free-kicks rather than playing on the PlayStation. That obviously changes. After training every day five years ago I would have been doing shooting and my finishing was fantastic. When you get older you can’t be hitting balls every day after training, so you have to develop. I will do yoga tonight when I get home.

“It is probably the worst saying in football when you are coming through – ‘You are busy, you’ or ‘You busy bastard’. It is not, is it? It is doing your job to the best of your ability and getting the most out of it. It is the norm now. Every single player in that dressing room is in the gym before training now doing their own stuff. Back then, or even at some other clubs now, you might get five to 10 lads in whereas here it is 25. And that is why the lads are at the level they are.”

Milner who shares fitness advice with fellow seasoned sportsmen and friends Jimmy Anderson and Kevin Sinfield, has witnessed a transformation in dressing-room culture. But, despite the “busy” comments, he believes the education he received at 16 was essential to prolonged success at the top.

“In that dressing room at Leeds you had the likes of Dom Matteo, David Batty and people like that. You had Wednesday and Sunday off so the lads mostly went out on a Saturday night, had team building on a Wednesday and some trained in a bin bag on the Thursday to sweat it out. On the other hand, some of the injuries I saw Dom Matteo play with – he was cutting holes in his boots to be able to play; he was in pain but just got on with it even with a grade two hamstring – it was a different time but there were pluses and minuses to both.

“The senior players looked after me so well in terms of shielding me from the press and making sure I didn’t do interviews too early. They would give me a rollicking when I needed it and I would make sure their boots were clean. It was a different way of learning to what the young lads get now but it wasn’t any worse, just different.

“I feel lucky to have been in both eras. I was playing in the Premier League and also picking slips [underpants] up off the floor, taking skips [for training kit] to the bus, cleaning the Under-19 captain’s boots and making the teas on the bus. You had to earn your stripes to get there. I feel lucky to have come through that and it helped, because you feel you have to earn the right to be among these guys.” That right must be earned at Liverpool. Milner makes sure of it.