Wales star Jamie Roberts knows from agonising personal experience that rugby can sometimes be the cruellest of pain games.

And it is why Roberts believes England will be "a massively dangerous side" in Friday night's Six Nations opener at the Millennium Stadium.

England's last Cardiff visit two years ago resulted in a record 30-3 defeat against Wales as their Six Nations title hopes and Grand Slam mission spectacularly unravelled.

Jamie Roberts has started ales' last 25 Six Nations games in a sequence that stretches back to early February 2010 © PA Photos

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"The hurt of those defeats motivate you," said 64 times-capped Roberts, who will be among 11 Wales starting line-up survivors from 2013 returning to face England again in three days' time.

"That's why they [England] are a massively dangerous side on Friday night. The players who played two years ago will be hurt by what happened.

"There is nothing more challenging than a wounded animal. When you go through those lows it's about how you react, and we will see a very good England side on Friday night. We will have to be on the top of our game.

"You can have amazing memories and low points as well. Losing to Ireland at home in 2009 [Ireland won the Grand Slam] was heartbreaking - it was probably the worst year of my career.

"Ronan O'Gara had a late drop to win the game in Cardiff, and then a few weeks later the [Cardiff] Blues lost the Heineken Cup semi-final by a drop-goal shoot-out against Leicester, and then we went out on the Lions tour to South Africa and lost the second Test with a last-minute kick.

"Three of the biggest games of my career did not end well."

Friday's clash - as if it needed ramping up - is given added spice by the fact that the next time two of rugby's fiercest rivals meet later this year, they will be in pursuit of World Cup points.

The dress rehearsal might have been diluted to a degree by England's alarming injury list, but Roberts, who has started Wales' last 25 Six Nations games in a sequence that stretches back to early February 2010, expects a fierce examination.

"Friday is going to be a huge test of everyone's abilities," he added. "It is a massive game, and you could not ask for a bigger test to start the tournament.

"It's about being clever. We can't afford to play too much against England, because they are very solid defensively.

"I have worked with [England assistant coach] Andy Farrell on the Lions tour, and he will be priming them to come full metal jacket at us. We will have to play smart rugby.

"We learnt from the autumn how important a good kicking game can be, and we can't afford to kick loosely to their back-three because Jonny May has some serious wheels and Mike Brown is a threat.

"People talk about their injuries, but the strength in depth they have in the league they play in means they can still field a strong team."

Roberts, 28, is arguably in the form of his life, relishing being part of a Racing Metro side that has powered its way into this season's Champions Cup quarter-finals as top seeds.

He also starred in Wales' autumn Test campaign in November, playing every minute of all four games against Australia, Fiji, New Zealand and South Africa.

"I have only played three times since November, which is nice, because I felt pretty battered after November against the three southern hemisphere teams," he added.

"I think I am playing as well as I have done during my career.

"Confidence is the main thing. Sometimes, when you are playing abroad you have to harness that confidence yourself, and that's difficult, especially with the language barrier.

"My first day back in Cardiff for the [Six Nations] campaign I got stopped more times than during the whole term out in Paris.

"It's nice because I am from Cardiff, and having people stopping and chatting with you reminds you of what an important thing you are doing for the country and that you are representing Wales.

"It's also nice being in Paris where you aren't recognised and people think I am just a tall lanky fella on a scooter. I stand out like a sore thumb because I don't dress like a Parisian."