Warrington's rookie full-back Matty Ashton has been given a ringing endorsement as he prepares to make his home debut, from the man whose place he has taken.

England international Stefan Ratchford made the switch to half-back for the Wolves' opening match against Wigan last week in the absence of new marquee signing Gareth Widdop and that paved the way for Ashton to make his Super League bow.

The 21-year-old Ashton, snapped up in the close season after scoring 30 tries in 25 appearances for Swinton in 2019, made an impressive debut in the 16-10 defeat, claiming a third-place point in the Man of Steel votes, and keeps the number one spot for the visit of reigning champions St Helens on Thursday.

"He's a great player, we've said that all pre-season," Ratchford said. "His speed is something else and he's only going to get better the more games he plays.

"He's a real exciting prospect and hopefully we'll see him grow in the next few weeks and years.

"Matty's still relatively new to the game, he's not played in the professional set-up for too long. He's still learning and he's keen to learn, he's not afraid to ask questions.

"He's happy to take advice on board."

Ashton said of his debut: "It's a dream come true, a really proud moment.

"I loved every minute of it and hopefully I can kick on and play many more Super League games."

St Helens will also have a rookie at full-back, with 18-year-old Jack Welsby taking over from Lachlan Coote, who sustained a knee injury in his side's big opening win over Salford.

The champions are still without skipper James Roby as well as Tom Makinson and Kyle Amor but have loose forward Morgan Knowles back.

Warrington have called up back row forward Ellis Robson for what would be his debut after losing skipper Chris Hill to suspension.

Saints will be strong favourites to start their title defence with back-to-back victories following their impressive demolition of the Red Devils but Ratchford says his side will take encouragement from the way they battled against Wigan with 12 men for most of the game.

"We were disappointed with the result but also quite proud of the way we played for 60 minutes a man down and we had 11 for a while but I thought the effort and work we did defensively was pretty good," he added.

"It doesn't get any easier this week. Saints were the benchmark last year with the consistency they showed, so we've got to raise the bar ourselves and match them and try and go above them.

"We know it's going to be a tough game but we've every confidence we can go out there and get the job done.

"There was a bit of a thing that Warrington could never beat Saints but the last few years the games have been getting closer and they are always nip and tuck. I'm sure it will be no different."