France fly-half Romain Ntamack has been ruled out of a home Rugby World Cup because of a ruptured anterior cruciate ligament.

France, who are hosting the World Cup, play New Zealand in the opening game on 8 September at Stade de France.

Bordeaux Begles' Matthieu Jalibert will likely replace Ntamack as France's starting fly-half.

Ntamack limped off the field in the second half against Scotland and underwent a scan on his knee on Monday.

The 24-year-old was widely regarded to be one of the stars of this year's World Cup, having scored a match-winning solo try against La Rochelle to help his club side Toulouse win the Top 14 title.

He is France's number one fly-half and featured in every minute of the side's 2022 Six Nations Grand Slam victory.

"It is absolutely devastating, especially when you are one of the home players, you have the opportunity to play at home and you are one of the favourites to win it," former England international Ugo Moyne told the Rugby Union Weekly podcast.

Ntamack also featured for France at the 2019 World Cup, where they reached the quarter-finals before losing to Wales.

He posted a message on Monday stating "I'll be back" following the news.

His father Emile, who played at the 1995 and 1999 World Cups, said he is "not worried" about his son's comeback, but admitted playing at a home World Cup is "very rare".

"It will take a little time to digest," he told AFP. "We are still a little in shock, even if he felt it coming since his injury.

"We were hoping for a pleasant surprise this morning (Monday) but we weren't under too many illusions. It didn't feel right. He had already taken blows to the knee and he felt it wasn't as usual."

French Sports Minister Amelie Oudea-Castera posted on Twitter that the national side would miss Ntamack's "flair".

"There's no doubt you'll be close by and that this dream belongs to you as well," she wrote.

France will also initially be without loose-head prop Cyril Baille, who will miss up to six weeks with a calf injury.