Joe Marler was not sure about Marcus Smith at first.

"I've been here 10 years and he's gobbing off at me, driving standards," Marler says, describing his thoughts at the time.

"I was like, 'He's this jumped up, entitled, private-school kid.' Then you realise how good he is at rugby."

To this day, there are few doubts over 24-year-old Smith's rugby ability.

But England head coach Steve Borthwick's decision to start the fly-half over Freddie Steward at full-back in Sunday's World Cup quarter-final against Fiji has raised some questions.

Steward has anchored England through some stormy seas since his debut in 2021.

Having been named England men's best player for the past two years, the 22-year-old was supposed to be a certainty for the red rose - until this World Cup.

Borthwick says including Smith at full-back was an experiment first discussed "some months ago". Sunday's game in Marseille will be the ultimate stress test of the logic behind it.

Team-mates have hyped up Premiership winner Smith's big-game mentality. That is what took Marler down memory lane in the first place.

"He's a big-match player," Marler said.

"He's had that early on. Even to the point where I've had to turn round and say, 'I'm going to have to say something to this guy.'

"He quickly earned the respect of the group because they know how good he is. I'm full of confidence in his ability to thrive on that stage, albeit in the 15 shirt.

"To have the attacking talent that he has, I'm full of confidence that he's going to perform this weekend."

Captain Owen Farrell, who along with George Ford has largely kept Smith out of the starting 10 jersey in the Borthwick era, agrees.

"I'm always impressed with Marcus," Farrell, whose inclusion at 10 over Ford is also controversial, said.

"I'm always impressed with how much he wants to get after it, wants the ball, wants to make a difference.

"From what I've seen so far, the bigger the occasion, the more he wants to do that."

Then there is what he brings to England's attack.

Smith has been working with Olympic great Daley Thompson on his speed and that is something that sets him apart from Steward.

Where Steward is sturdy against a barrage of high balls and an on-rushing attack, Smith brings play-making wits to help puzzle his way through tight-knit defences.

It seems to be these points of difference that have worked in Smith's favour.

"In terms of the selection process, I analyse the opposition with my coaching team," Borthwick explained.

"We go through exactly how we want to play then select the team accordingly.

"The strength of the players in our back three - it's great to have the different combinations of strengths.

"This starting back three is the right one for the game this weekend."

The experiment went well against Chile.

Smith started that game at full-back and, after some initial errors, showed the individual brilliance he can bring to the role.

He shot into some space, sent a testing kick through and got to the ball first for his try.

Smith reshaped England's attack as he worked alongside Farrell - and later Ford was introduced to give Borthwick's side three play-makers on the pitch.

Chile were the lowest-ranked side in the tournament. Fiji are ranked 10th but have proven their ability to beat big names in recent weeks - adding Australia to their list after a first-ever victory against England at Twickenham in August.

Former England captain Matt Dawson describes Borthwick's style as "risk-averse". This selection would suggest otherwise, but Borthwick has seen enough to feel convinced.

"Marcus is a top-quality rugby player, he has played plenty of Test rugby," Borthwick told BBC Radio 5 Live.

"Every time he has come on to the pitch, and in his start against Chile with 15 on his back, he has played brilliantly. What he brings is what we need this weekend."