Rugby World Cup 2023: Ex-Ulster back Piutau relishing Tonga's Ireland challenge

Piutau celebrates scoring a try against Clermont in 2016, which he said was a highlight of his time with Ulster

Tonga's Charles Piutau says he's looking forward to facing former Ulster team-mates when he makes his World Cup debut against Ireland on Saturday.

The full-back played with Ireland trio Stuart McCloskey, Iain Henderson and Rob Herring during a two-year spell at Kingspan Stadium.

"I've very good memories," said 31-year-old Piutau.

"It feels weird that some of the guys I'll be playing against were part of that team, so it should be good fun."

The former Wasps and Auckland Blues player was a fans' favourite as an utility back for Ulster before moving to Bristol in 2018.

"The chant [Stand Up For the Ulstermen] always comes to mind running out of the tunnel - the guys that were there, they were awesome and made me feel welcome," added Piutau.

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Piutau saw close up the ability of McCloskey, Henderson and Herring and he rates the trio highly as preparations continue for Tonga's opener against the Irish in Nantes.

"I was lucky enough to play with Stuart at Ulster - I always knew he was good enough and should be playing for the national team," he said.

Charles Piutau and Stuart McCloskey celebrate a European Champions Cup win over Harlequins in 2017

"He always said he wanted to be like Sonny Bill Williams with his offloads and I've seen him continue to work on that. He's developed his game really well.

"What a player, what a talent Iain is and a great leader when I was at Ulster. Just his strength on that field - he sometimes wouldn't lift the heaviest in the gym but he just has that natural strength and work-rate around the field.

"Rob is another guy who I always thought was on the fringe when I was at Ulster but to see him consistently involved for Ireland is a credit to him. It's awesome to see the guys I played with at Ulster get regular game-time and being a big part of this Irish team.

"I'm sure they will be telling everything about me [to the Ireland team] but that's the fun about it and it will be good to see them on that field."

Piutau played 17 Tests for the All Blacks between 2013 and 2015 but new eligibility criteria gave him the opportunity to switch to Tonga.

He's poised for a first World Cup appearance and knows just how tough a challenge it will be against Ireland, who started with an 82-8 hammering of Romania last weekend.

Charles Piutau switched allegiance to Tonga and will make his World Cup debut on Saturday

"It's our first game and what better way to test yourself than against the world number one ranked team," added Piutau.

"It's an exciting challenge ahead of us. Although Romania scored first you just saw the composure, the structure and talent Ireland had.

"They were very clinical when opportunities came and you can definitely see why they are the number one seeded team in the world."