Wales centre Jamie Roberts says Bath team-mate Ruaridh McConnochie "could not ask for a higher pressure environment" for his England debut than a sold out Principality Stadium.
The wing, 27, will start in Saturday's World Cup warm-up against Wales.
McConnochie converted from sevens last summer and is now part of Eddie Jones' squad for the World Cup in Japan.
"He'll make his Test debut in the cauldron that is the Principality stadium in Cardiff," said Roberts.
"He played in an Olympic final [at Rio 2016] as a sevens player so he's experienced that testing atmosphere in big rugby games.
"He's adapted to XVs so quickly, he now has to adapt to Test match rugby far quicker over the next month."
McConnochie came away from that Olympic final with silver and was part of the England side who came second in last year's Rugby World Cup Sevens.
Also a Commonwealth Games bronze medallist, he played for Kent side Cranbrook in the sixth tier of English club rugby as a teenager, but made an impact on Roberts at Premiership side Bath last season.
"The biggest thing that impressed me about Ruaridh is his work ethic and his desire to learn," added the 32-year-old on BBC Radio 5 Live Sport's Matt Dawson's Rugby Show.
"You don't see that too much in young players. He's quick, very deceptively quick, and strong. In games for us last season, he was punching well above his weight.
"He's fantastic in the air. Being able to win the ball back in the air is a massive part of Test rugby now. He runs 100% into contact. He's relentless."
'You need a scrum-half who can pull out basics in big games'
Scrum-half Willi Heinz earned his first England cap in the side's victory against Wales at Twickenham last weekend, but the Principality crowd will be a new experience for the 32-year-old too.
Despite only one international appearance, Heinz is part of the World Cup squad along with starting scrum-half Ben Youngs and former England number nine Matt Dawson thinks this could be down to his ability to remain calm under pressure.
"Eddie Jones wants a certain type of nine in his squad," said Dawson.
"I think Willi Heinz is probably the only player who can challenge to start the game ahead of Ben Youngs. I think that will bring more out of Ben.
"The World Cup is not won in the pool stages, it's probably not won in the quarter-finals. You have to have players who in the biggest games of their lives can pull out the basics."
After Saturday's match, England will play warm-up games against Ireland and Italy before their first World Cup match against Tonga on 22 September.