Having faced the two "extraterrestrials" in league football this season, the Sevilla star is acutely aware of just how potent they can be
Denmark captain Simon Kjaer has picked his favourites to win the World Cup, and although Argentina and Portugal are not among them, he believes that the influence of Lionel Messi and Cristiano Ronaldo can lead them to glory.
Kjaer plays his club football at Sevilla and is well versed with coming up against the game's best players.
Messi and Ronaldo, however, are special in his view and can elevate the level of whole teams above the ordinary.