How can Messi's Argentina and Ronaldo's Portugal face each other in FIFA WC quarter-finals?

Lionel Messi-led Argentina have qualified for the FIFA World Cup 2026 knockouts after topping Group J. Cristiano Ronaldo-led Portugal are currently second in Group K but can still finish first. The teams can meet as early as the quarter-finals if Argentina win their Round of 32 and Round of 16 matches, and Portugal do the same after topping Group K.