Leigh Halfpenny insists he had to leave Wales in order to win trophies.

The Wales full-back lines up against his old club Toulon on Sunday as the Scarlets travel to France in the opening round of the European Champions Cup.

For Halfpenny it will be an opportunity to catch up with old friends and to reflect on his decision to return home after three years spent on the lavish payroll of the former European champions.

“I’m looking forward to going back out to Toulon with the Scarlets and after the game catching up with some of the guys that I played with during my time there,” he told Sky Sports News.

“But during the game it’ll be a huge battle, that’s the exciting part.

“When I made the decision to go it wasn’t an easy decision to leave Wales but I felt at the stage of my career, and how things were, that was the right time to go and win silverware.”

The British and Irish Lions’ Player of the Series in 2013 endured a mixed spell in France after quitting the Cardiff Blues, capping his first season with the club by conquering Europe, before a serious knee injury ruled him out of the World Cup and most of the following season.

Halfpenny was not available for Toulon’s Top 14 final defeat last season because he was released to link up with the rest of the Lions squad ahead of their tour to New Zealand, a move which persuaded Toulon president Mourad Boudjellal not to proceed with the offer of a new contract.

The 28-year-old’s only appearance against the All Blacks came as a replacement in the first Test, but he has begun his Scarlets career in convincing form and he will form a key part of the Guinness Pro14 champions’ European strategy as a defensive pillar, an increasingly confident attacking threat, and a deadly goal-kicker.

The Scarlets are in a difficult looking Pool Five, but one that also offers opportunities for the Pro12 champions. They are joined by three-time European champions Toulon, 1998 champions Bath and Italy’s sole representative, Benetton of Treviso.

Despite the Scarlets’ magnificent achievements domestically last season, they have yet to make it out of the pools in Europe since 2007, and will be focused on creating European success to go along with their league achievements.

Toulon have endured a difficult couple of campaigns to follow on from their historic three titles in a row, but have loaded their squad with yet more stars in the close season, and look a fearsome opponent once again.

Only once since the 2005/06 campaign has there been a year in the European Cup (2012/13) where a pool containing an Italian side has not produced two quarter-finalists, but that could change this season with Benetton in their best run of form for years.

Toulon were victorious in France over the Scarlets last season on December 11, 2016 with Halfpenny converting all four tries and kicking a penalty against his future employers.

However, the Wales fullback had a far less enjoyable time at the return leg in Llanelli the following week as despite scoring all the visitors’ points in a 22-21 loss, his last-minute penalty miss would have won it for the French side.

As Halfpenny returns to his former club, his back three colleague Johnny McNicholl will be playing in France in Europe for the first time.

“They (Toulon) always have big name players. I watched them play here last year and us get the win but it would be nice to go there and get the win in their back yard,” said the New Zealander.

“Personally I’ve only played one game in Europe, against Sarries last year, but the week leading up to it was a bit more intense and the game itself was a bit of a step up. We were really on the ball and really wanting to perform well and show everyone else what we’re about.

“Our challenge is to at least make the play-offs in Europe this year and go that one step further. It would be nice to prove ourselves.

“It’s enjoyable to play in a team with width, giving the backs freedom to play and do what we do best really.

“It’s enjoyable. We haven’t hit 100% yet but we’re still working towards that.”