The French forward is only 23 years old and the world could see him winning the showpiece tournament for the second time.
Much has been said and written about Mbappe's skills on the pitch, including his dribbling ability and speed.
His opponents at the current tournament spoke extensively about their experience before and after facing him.
Polish midfielder Piotr Zielinski said, "I had obviously seen him a few times on TV, but there is a big difference between watching him and facing him.
"On the pitch, he seems even more unstoppable. He is an extra-terrestrial," he concluded.
Matty Cash, another Polish footballer, and defender, detailed the homework he did to stop Mbappe when he said, "I spent the afternoon watching his clips and I knew it was going to be a tough test. When he gets the ball, stops and moves, he’s the quickest thing I’ve ever seen. I’m watching the videos while lying in bed! In real life, he’s burning my legs – that’s the difference."
After Poland's defeat to France in round of 16, Cash managed to get his hands on the PSG striker's jersey.
Lionel Messi, on the other hand, has been Argentina's standout player in the competition, further justifying why he has been called the greatest of all time for the longest time by many football pundits and fans.
Mbappe is much younger and has a few more World Cup tournaments in him. He is much better placed to take over that mantle from Messi. Furthermore, he has already overtaken Cristiano Ronaldo's tally (8) of World Cup goals and is only two shy of Messi's (11).
Les Blues striker has spoken in the past about his obsession with winning the tournament. He even refused to speak to the media during the group stages, for he feared it could distract him from his goals.
In addition to winning the tournament trophy, the Golden Boot hangs in the balance too with both Mbappe and Messi tied now with 5 goals each.
An Argentina victory could definitely end the GOAT debate once and for all cementing Messi's legacy. A French win, on the other hand, will see Mbappe seeping into the debate.