
Mbappé scored twice in France's 6-4 defeat to England in Saturday's third-place playoff, taking his tournament tally to 10 goals. Messi has eight goals, leaving him needing at least two goals in the final to draw level and three to move ahead.
Before the third-place match, Messi and Mbappé were tied on eight goals, with the Argentine leading on the tiebreaker thanks to one more assist.
If Messi cannot overtake Mbappé, he is still widely expected to win the Golden Ball, awarded to the tournament's best player. At 39, he has guided Argentina to a second consecutive World Cup final and is already the only player to have won the award twice, having claimed it in 2014 and 2022.
"He is history. He is a legend," Argentina coach Lionel Scaloni said.
The Golden Boot is the only major individual World Cup honour missing from Messi's long list of achievements, which includes a record eight Ballon d'Or awards.
Mbappé, who won the Golden Boot at the 2022 World Cup in Qatar despite France losing the final to Argentina, became the first player to score 10 goals in a single World Cup since Germany's Gerd Müller achieved the feat in 1970.
If Messi scores enough goals to surpass Mbappé and Argentina win the title, he would become the first Golden Boot winner to play for the World Cup champions since Brazil's Ronaldo in 2002.
Spain also have strong contenders for the tournament's other major individual awards.
Goalkeeper Unai Simón is among the favourites for the Golden Glove after conceding just one goal in seven matches, while 19-year-old forward Yamine Lamal is a leading candidate for the Best Young Player award, presented to the top performer aged 21 or under.
The Golden Ball, Golden Glove and Best Young Player awards are decided by media representatives from a shortlist prepared by FIFA's Technical Study Group, reports UNB.