England U20 World Cup winner Nick Tompkins will run out at Twickenham in the red shirt of Wales on Saturday and admits it is a surreal prospect.

Six years after helping England's young guns achieve global glory, he now faces potentially the toughest test of a fledgling senior international career.

Sidcup-born centre Tompkins – he qualifies for Wales via his maternal grandmother, who hailed from Wrexham – will oppose six of his Saracens team-mates in England’s matchday 23.

It will be only the 25-year-old’s fourth Wales appearance, yet he has already shown enough glimpses to suggest new head coach Wayne Pivac might have unearthed a gem.

Tompkins won an U20 World Cup with England

And the Tompkins family will be out in force as Wales target a first Six Nations away victory over England since 2012.

"Dad has to wear the red jersey or else he can’t come!" said Tompkins. "They are all coming, yeah. All my friends. Loads of people wanted tickets.

"I think you can get more than two or three tickets, but then you start having to pay. It starts racking up. I don’t love them that much!

"It does feel surreal (playing against England) and I suppose it’s not going to kick in until I am really there."

Saracens colleagues Owen Farrell, Maro Itoje – Tompkins' England U20 captain – Elliot Daly, Jamie George, George Kruis and Ben Earl will all be out to ruin his day.

But Tompkins has now joined an exclusive club of modern-day Saracens international players, even if it might have taken him a little bit longer than some of England’s established names.

Tompkins scored a try on his Wales debut against Italy

"I would say that was one of the hardest things I had to go through," he said.

"You see all these guys, they make it. The opportunities they’ve had, they’ve taken them.

"You question why you are not getting the opportunities, but I think it clicked later on that there were things I needed to do and I wasn’t doing them.

"I was probably blaming other people, making up excuses for why I wasn’t doing what I should have been doing.

"I started taking control, doing it right. It is tough as a young kid being at a good club with players like Brad (Barritt) and Duncan (Taylor), who are so good.

"You have to be patient, and I realise looking back that everybody has got their own path. I wasn’t ready then. I am ready now, but I don’t know if I would have been ready if I had been thrust in to Test rugby at 22 or 23.

"I want to show people why I am here. I want them to see that, 'yes, he deserves to be here’."

Tompkins made a try-scoring debut off the bench against Italy last month and although he endured a testing afternoon in defeat to Ireland a week later, he then excelled in Wales’ thrilling encounter with France.

"The standard of rugby is obviously a little bit higher but the biggest thing for me is the hype around it," he said.

"The stuff that is not to do with rugby. The pressure, things like that. It’s something that you just learn and get used to."

And asked if he had felt an extra edge to Wales training this week, a laughing Tompkins joked: "Yeah. There’s a lot of hatred for the English!

"I’m a lover, not a fighter, but you can feel the anticipation, you feel a bit of edge, which is great."

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