Kyle Sinckler is grateful to Alun Wyn Jones' Wales for the provocation in Cardiff a year ago that forced him to curb his ego and stop acting as the bad boy of English rugby.
On that day Sinckler eventually reacted to repeated wind-ups from Jones by conceding two penalties in quick succession that contributed to a major momentum shift as a commanding half-time lead crumbled into a 21-13 defeat.
Wales went on to be crowned Grand Slam champions – a prize Sinckler believes would have belonged to England had he kept his cool and not justified Warren Gatland's description of him as an "emotional timebomb".
It is a harsh assessment given he was outstanding until he was replaced on the hour mark, Eddie Jones sensing the red mist was about to descend.
Revenge was taken in the shape of Saturday's 33-30 Guinness Six Nations victory at Twickenham that saw Sinckler shrug off renewed attempts to antagonise him having spent months addressing the personal issues that fuelled his rage.
"I'm very, very thankful for what happened in Cardiff because without that I'd probably have kept costing the team. At half-time my ego was bigger than this room," Sinckler said.
"Looking back on it, I really enjoyed being that villain – the bad boy of English rugby. I was just very angry. Very, very angry. I had to harness that and do something positive and understand why I was angry and kept making the same mistake.
"Cardiff was perfect. It was exactly what I needed. It was sink or swim because if I didn't change then I wouldn't have played for England any more.
"I definitely cost the team a Grand Slam and I probably cost everyone a shed-load of money in bonuses. I was so in denial. I never took responsibility for what happened.
"I was saying 'life is hard, it wasn't my fault, the referee doesn't like me, in Cardiff you're never going to get the rub of the green'. But when you strip it back and look at it, it was just ego.
"It was ego trying to get in with Alun Wyn Jones, trying to be that bad boy which cost the team. Now hopefully everyone can see – and I know myself – I am a different person.
"I thank Warren Gatland and I thank Alun Wyn Jones because I feel I have grown from it and I'm only going to get better.
"The same kind of situations were happening on Saturday in terms of them holding me down, someone stamping on me when I was getting up, or certain things said, but it made no effect.
"In the past I always had to get one up on people or confront people, but now if you target me that's wasting energy on me. I'm fine, I'm not exerting any energy, I'm doing my job.
"If two players are on top of me, that's sweet, because then there will be two fewer guys in the defensive line."
Hoping to inspire young athletes from the tough south London neighbourhood where he grew up, Sinckler is launching a foundation called 'R3cusants' designed to provide financial assistance to those with potential.
"I've got to thank all the knowledge I've received from Saviour World, especially my mentor who has helped me out a massive deal," Sinckler said.
"We spoke last Sunday and in my own head I wanted to dedicate this Wales game to my foundation that I'm setting up.
"My issues were never anything to do with rugby, rugby was always my canvas. It was always stuff outside of rugby and the aim of my foundation is to help kids in inner-city London and give them the opportunity.
"My biggest gripe is that there are guys who I went to school with who didn't have the means, transport or parents pushing them, or the kit or the facilities. If you look at the talent that's in inner-city London, it's an untapped reservoir."