Ben Spencer was feeding his children at home when he received a phone call inviting him to join England's squad for the World Cup final.

The Saracens scrum-half, who watched the semi-final victory over New Zealand on television, starts on the bench against South Africa after replacing the injured Willi Heinz.

He admits it has been a "crazy few days" but has "loved" the experience.

"I trained all week with Saracens, and was due to play Leicester," he said.

"I was just at home, feeding the kids, then got the phone call on Saturday afternoon, was on a flight Sunday morning, and arrived Monday morning.

"The kids are a bit too young to understand, but my partner was thrilled. They actually got here [to Japan] this morning. It's an exciting week for all of us."

Spencer will provide cover for Ben Youngs against the Springboks in Yokohama on Saturday when England aim to become world champions for a second time.

The 27-year-old made his England debut on tour against South Africa in 2018 and was influential as Saracens were crowned English and European champions last season.

He narrowly missed out on World Cup squad selection but says he is not "too out of the loop" after spending time with the squad in pre-season,

He added: "It's not been too difficult to get up to speed, and Benny [Youngs] and Willi [Heinz] have helped me out with what is going on this weekend.

"In terms of the jet-lag I've actually been OK. The first night was tough, but I seem to be in the swing of things now."