The Scarlets travel to the Stade Mayol to take on a Toulon side that will contain a certain familiar face as part of their star-studded back-line.
Halfpenny made his first start for his new team in their 21-10 defeat at Toulouse after recovering from shoulder and groin problems that had sidelined him since March.
And he will go head-to-head with in-form Williams, who’s stock has risen since deputising for the former Blues man last season. But Williams is keeping his own house in order ahead of the Champions Cup kick-off this weekend.
He said: “I’m really close to Leigh off the field, we get on really well. I’m not looking too much at him to be honest. I will be going out there to play my own game.”
“Personally, this season hasn’t been too bad apart from the two yellow cards at the beginning,” added Williams.
“As a squad we’ve been close but just haven’t found that edge yet with the finishing touches and passes. Hopefully it will all come together.”
The 14-cap full-back’s bright start to the season was interrupted by a red card in their PRO12 opener against Ulster. But he has gone from strength to strength and despite the Scarlets failing to shine so far, Williams has earned plaudits for his abrasive performances. And he is hoping to continue that form at the home of the European champions.
He said: “What’s happened up until now in the Pro12 has gone and we have to concentrate on the game that’s ahead. Last season our Pro12 form hadn’t been great up until that point but we went out and turned it on against Harlequins which nobody expected.
“Sunday is the start of one of the biggest stages of the season for us and it would be great to get a win. Toulon are Champions Cup giants. We will go out there and give it our all.”
