But only one of those teams can make it to the final.
France and Spain are both playing at their 17th World Cup, but have met only once previously on soccer's biggest stage. They face off on Tuesday (5am Wednesday AEST) at the home of the NFL's Dallas Cowboys in the first of two semi-finals.
FIFA's top-ranked team France have outscored their opponents 14-2 in the US. Mbappe, the 2022 Golden Boot winner, has eight goals to match Lionel Messi, and is one behind the Argentina captain's career record of 21 at the World Cup.
"We are focused," Les Bleus midfielder Adrien Rabiot said.
"We are confident, of course, with the course we have done so far, and we have to be, but always with this humility that has characterised us since the beginning of the competition."
The 27-year-old Mbappe has 20 goals in 20 World Cup matches, including one in the 2018 win over Croatia when he joined Pele as the only teenagers to score in a World Cup final.
Yamal, who turned 19 on Monday, has already been part of two semi-final wins with Spain over France. He was still 16 when he scored in a 2-1 win during the 2024 European Championship and then in a 5-4 Nations League victory last year.
Spain have outscored opponents 10-1 since a stunning nil-all draw against Cape Verde to open group play, but La Roja needed late decisive goals from Merino after he entered the last two games as a second-half substitute. All while goalkeeper Unai Simon set a World Cup record of 650 minutes without conceding until Belgium found the net in their quarter-final.
"I think that from the first game until today, the team needed to catch the rhythm, we had been without seeing each other for a long time," Spain midfielder Alex Baena said, adding that with more games and practice "the better the team have been."
Merino scored in the 88th minute for that 2-1 win over Belgium. That came after the Arsenal forward's goal in second-half added time for the 1-0 win over Portugal in the round of 16.
In their only previous World Cup meeting, France beat Spain 3-1 in a last-16 game at the 2006 tournament in Germany.
Both teams have won the World Cup since then, Spain in 2010 and France in 2018.
France, who will be playing on Bastille Day, are trying to join five-time champions Brazil and four-time winners Germany as the only teams to make three consecutive World Cup finals. Brazil did it in 1994, 1998 and 2002 — winning twice and losing to hosts France in the middle of that run. Germany's championship in 1990 came after being runners-up in the previous two World Cups — all as West Germany.
Argentina beat France on penalties in 2022 after it finished 3-3.
This is France's seventh semi-final appearance and fifth in the last eight World Cups. Spain's only other semis were in 1950 and in 2010.