But it wasn’t just that. His whole family got involved in the celebration, with his inspirational grandfather being invited by the Welsh management team to present Leigh with his special jersey at the team hotel the night before the game.
There was a huge family gathering in one of the hospitality boxes to cheer on the 34-year-old Wales full back during the game and his two young daughters, Nora and Lily, accompanied him onto the pitch after the 20-9 victory to help him conduct his interviews.
His fiancee, Jess, sent him an emotional address featuring their children to add further motivation, and tears, to the occasion, and then there was a hero’s welcome for him at Principality Stadium as he ran out on his own ahead of the two teams to receive the applause and appreciation of an admiring nation.
It was a long way from his first visit to the home of Welsh rugby back in 1994, when his aunty took the then five-year-old Leigh to watch his first game at the old National Ground, Cardiff Arms Park as Wales met South Africa.
It’s a family thing, Welsh rugby, with everyone helping to inspire, support and nurture a love of the game in their youngsters. What began with his ex-RAF grandfather, Malcolm, taking him to Gorseinon rugby club from junior school for kicking practice, paved the way for a haul of 795 points in 100 games for his country to date.
“It was my aunty who took me to my first game at the old Cardiff Arms Park. I remember being in the stands looking out and dreaming of being out there one day,” said Leigh.
“It was a dream come true to win my first cap for Wales and I can’t really put into words how much it means to win my 100th. It’s down to a lot of people who have helped me along the way to achieve this.
“There have certainly been some ups and downs along the way with injury. There have been some really tough moments, times when you weren’t too sure whether you’d get back on the field and play for Wales again.
“It all made it such a proud day for me against England. It wouldn’t have been possible without so many people around me, all the coaches in my career, my teammates and the medical staff – they’ve all been superb.
“It’s the same with my family and friends. Jess, my fiancée, and my two girls – they’ve been my rock, to be honest. They’ve kept me going and I’m incredibly grateful to everyone who has helped me achieve this.”
The opening game of the three World Cup warm-up matches for Wales was far from a farewell for leigh, more an audition for a third trip to the global tournament. He’ll surely be back for more – and definitely wants more!
“It was a pretty special day for myself and my family. Winning one cap for Wales was a dream come true, but this is surreal and hasn’t really sunk in yet,” he admitted.
“I’ve got to give huge thanks to Warren Gatland for giving me my first cap and awarding me my 100th. I’d obviously love to carry on playing and the ambition is to keep going.
“I’d love to go to the World Cup in France but there is so much competition in the squad and in the back three. There is a lot of quality and I’m sure whoever is picked will do an outstanding job.”
More than two hours after the game had ended, Halfpenny appeared in the mixed zone to speak to journalists about his memorable day. He was wearing his third Welsh cap – received to mark his 100th appearance in the same way he was awarded one after his first and 50th caps.
In typical unpretentious fashion he talked the media through his day and explained how he had marked his latest landmark in the dressing room with a song that took him all the way back to his club roots.
“After my first and 50th caps I sang ‘Walking in Memphis’ to the boys. This time I chose ‘Silver Dollar’,” he explained.
“It’s a song we sang in Gorseinon when I was a kid coming through. You’d hear the adult boys singing it and you’d learn it – it’s a favourite among my friends and it’s a song close to my heart.
“It felt right to sing that. It was quite a full changing room so there were a few nerves.”
Among his teammates on the field after the 20-9 win over England was someone who had been with Leigh all the way through the ranks. Dan Biggar played with him in the club’s junior ranks, and also won Wales U16, U18, U19, U20 and senior caps alongside him.
“We now have 208 Welsh caps between us – not bad for two boys who played for Gorseinon Under 13s together,” Biggar told BBC Wales.
“It is incredible to think that only nine players have played 100 internationals for Wales and two of them have come from one small club in Swansea. We had a great age-grade system at Gorseinon, and everyone should be proud of Leigh.
“He is a complicated and complex guy and puts a lot of pressure on himself. He wants every team, performance, training or gym session to be perfect.
“That has probably got him to where he is today. He is as level-headed, hard-working and dedicated as anybody you will find.
“I don’t think anybody deserves 100 caps more for his sheer commitment to not giving in. He would have probably been well past this landmark without the number of serious injuries he’s suffered.”