In a glittering 17-year professional career that took him all over the world with some of rugby’s most famous clubs, Jamie Roberts quickly became used to pressure.

The former Wales centre played in some extraordinary sides – ones in which teamwork, learning and respect, among other things, all played a role. Now, in retirement, Roberts is still practicing those traits.

The big difference is he has swapped a rugby field for a hospital ward. Earlier this month, 12 years after graduating with a degree in medicine, Roberts began his new life as a junior doctor with the Cardiff and Vale Foundation Trust.

On the field, Roberts never took a backward step as a physical, uncompromising centre. So, it is no surprise he has thrown himself headfirst into his next challenge too.

‘I’m really conscious I don’t want rugby to define the second half of my life,’ Roberts, now 38, told Daily Mail Sport. ‘It defined the first half and has given me everything I’ve got.

‘I’m so grateful to the game for that. When you stop as a player, the easy thing is to hang on to that. But I’ve still got 30 years of my working life ahead. You don’t think about things like that during your career. Then you retire and think “S***, that’s a long time.”

‘I’ve always been someone who has deliberately taken themselves out of their comfort zone as for me, that’s where life is meant to be lived. ‘I love science and problem solving, but being a doctor for me is about taking myself out of my comfort zone and doing something different.

‘Every player goes through this when they retire. But I took a bit of a deep dive to see what really made me tick. When I did that, I realised I still love pressure.

‘I still love learning and being part of a team. I love being around people. There’s a reason for that. Those things made me tick in a rugby environment, so it’s only right I give them a try elsewhere. To me there is nothing worse in life than wasted potential. I think a big part of me would have regretted it had I not become a doctor.’

Roberts certainly didn’t waste his rugby potential, starring for Wales in one of the country’s golden periods where Six Nations trophies and Grand Slams were commonplace.

Earlier this month, after returning from this summer’s British & Irish Lions tour of Australia, he took a giant step into the unknown. Roberts is now working four days a week as what is officially known as a ‘resident doctor’ and will do so for the next two years. It allows him to stay involved in the game he loves through media work and his role as a non-executive board member with the Welsh Rugby Union.

We meet for lunch on Roberts’ day off, the same day the WRU announced its preference to cut the number of Wales’ domestic teams from four to two. It is tough times for the Welsh game currently.

‘The first couple of weeks have been crazy,’ said Roberts, whose current focus is medicine. ‘I’ve been involved in a resuscitation where unfortunately the patient didn’t make it, a collapsed lung and a patient who had a fitting condition. That’s come quite early. But it’s part of the job. I’ve probably used my mind more in the last two weeks than I have in the last two years and that’s given me great pleasure because it’s what I enjoy. I’m stretching myself.

‘You can never know everything as a doctor. It’s not possible. I’m doing at 38 what the majority of medical graduates do at 23 or 24, so my working cohort are a lot younger than me. It’s actually been refreshing. I’ve enjoyed being around younger people. It keeps me young!

‘It’s amusing when some of my colleagues realise they're working with me. Others don't have a clue I played rugby. It is funny to see their reactions when patients stop me and ask for photos. That’s maybe a bit weird, but I don’t mind it one bit.

‘You can see the joy it brings patients to talk about rugby. It shows the passion people still have for the game in Wales. If doing that with me brings joy to them while they’re in hospital, then that’s amazing. I keep reminding my colleagues I’m just a kid from Cardiff who used to be good at rugby.

‘That was my past life. Now we’re in real life.’

Whether it’s playing rugby at the highest level, jamming with the Manic Street Preachers or tending to patients’ needs, Roberts has always lived life at full speed. And he isn’t slowing down yet. If anything, he’s speeding up.

He has three children under four and credits his ‘superhero’ wife Nicole for her support. After our lunch, Roberts has a date with the tip to remove some garage junk. During our chat, his phone buzzes repeatedly.

There is barely time for Roberts to wolf down his burger and chips. ‘I love stress,’ Roberts, whose six junior rotations will include trauma and orthopaedics and accident and emergency duty, among others, said. ‘And starting life as a junior doctor is a lot of stress!’

His long-term goal, as things stand, is to become a surgeon – one driven by his immense respect for those who wield the knife and the numerous operations he had to fix injuries during his playing career.

Roberts continued: ‘I still have pressure. In medicine, it comes from doing right by the patient. It’s been in at the deep end. But I’ve loved it. I do my first overnight shifts this weekend, so that will be another challenge but one I’m looking forward to.

‘I’m working as a doctor 80 per cent of my time because I have a young family, but also because I want to stay involved in the game. It’s given me so much.

‘I want to give back to it. Part of me would love to coach one day. I’m involved in the media which I enjoy. The WRU board stuff is great. I’m non-executive which brings pros and cons. I still have a huge passion for Welsh rugby. We all want it to be successful and for Wales to get back to the top.

'I played in some bloody good teams and when I look back, the best thing about them was they were full of people ready to speak their mind and enjoy healthy challenge. I’m never afraid to do that.

‘I hope that will carry me well in medicine and in life.’