The England head coach, Simon Middleton, has insisted he had no qualms over shifting Emily Scarratt to full-back for Saturday’s Women’s Rugby World Cup final against New Zealand after Danielle Waterman’s absence again called into question the quickfire nature of this tournament.

Waterman was withdrawn during the first half of Tuesday’s semi-final victory over France for a head injury assessment (HIA) and failed to return. With the final coming only four days later, Waterman was unable to complete the return to play protocols and was immediately ruled out.

Her absence is a blow for England – this has been Waterman’s fourth World Cup and she is the only member of the squad to have started all four matches – and it means Scarratt, an outside-centre by trade and the match-winner in the 2014 final against Canada, must fill the void.

Megan Jones slots into the No13 jersey in the only change to the England XV and Middleton has revealed it was a straightforward decision, considering Jones’s form from the bench against France.

“Emily is quite an accomplished full-back, she’s played there a lot,” Middleton said. “And when Jonesy has come in, she’s played really, really well at 13, she gives us a really good balance to the side in terms of she’s quite an aggressive defender, so she’ll get us on the front foot. And with Emily at full-back it gives us a little bit more of a kicking game from there.

“[Emily] could play anywhere really. I think 13 is probably her strongest position at the moment because she’s played there so often. But it will add a slightly different dimension to our game because she’ll be a little bit wider and she can pick and choose when she comes in a little bit more. She’s a very accomplished back and I have no doubt she’ll go well.”

The fact that Waterman had no chance of featuring in the final again raises issues over the format of the tournament. The final will be a fifth match in 18 days for England and New Zealand, and such a relentless schedule led the USA head coach, Pete Steinberg, to make accusations of discrimination. Additionally, New Zealand’s star winger Portia Woodman, who has 13 tries so far, has said: “I’d like to see the men do a tournament like this.”

Middleton added: “It goes without saying, if we could have had an extended period to get a player like Danielle fit again, and through the protocol we’d have loved to have had that, but that’s not what we’ve got and it’s very much about dealing with the situation as it is. We’ve said all along we’re really confident in the squad. It’s one of those things, all teams have had setbacks throughout this competition and we’re quite comfortable with how we’ve gone through it.”

While England are the defending champions, New Zealand have never lost a World Cup final and lifted the trophy four times in a row from 1998 to 2010. As part of a 13-match unbeaten run, England won in New Zealand for the first time in 16 years this summer while their last defeat was by the Black Ferns in November.

It means a close contest is expected but England’s captain, Sarah Hunter, believes her side are ready to go the distance. “Getting to the World Cup final for any squad is the ultimate test,” she said.

“Past form really goes out the window, we’re not thinking about what games we’ve won recently or what games we’ve fallen short in. This tournament has been about this squad and how we can go and put our best foot forward. Every time we’ve taken to the field, we’ve got better and we’ve got stronger. There’s a feeling that we’ve still got our best game to come.

“We prepare as best we can and we’ve got every scenario covered. We know that like the semi-final, it’s going to be a really close game, a really tough game. We know that we’ve got the patience within ourselves to play like that.”