3 key battles to watch in Euro 2016 final

Portugal and France arrived in the final of Euro 2016 for different reasons. The Portuguese frustrated opponents with a stifling brand of football, while the French emerged as an attacking juggernaut largely thanks to the dynamism of Antoine Griezmann.

That's why Sunday's showpiece will see a clash of styles. Portugal manager Fernando Santos has proven himself a masterful tactician over the past few weeks, using all 20 of his outfield players to make sure the right ones execute his game plan.

But the constant amidst Santos' tinkering is the 4-4-2 formation, which sometimes evolves into a 4-1-3-2 system. The midfield diamond is what allows Portugal to utilise the wings and still keep a defensive shape, with one of William Carvalho or Danilo in front of the defence.

Unlike Santos, French counterpart Didier Deschamps has only recently found his best lineup. Now deployed behind Olivier Giroud in a 4-2-3-1 formation, Griezmann is the key to France's success.

Related: 4 key questions heading into the Euro 2016 final

All of the above could cancel each other out and produce an utterly unspectacular final. Portugal - the purveyor of strict, defensive football - wouldn't have it any other way.

But France, with Paul Pogba and Blaise Matuidi also showing a penchant to push forward, could also help expose Portugal's midfield.

Here are the three particular matchups that will tell the story of this final:

Bacary Sagna vs. Raphael Guerreiro

One of Portugal's primary strengths is on the flanks, and the full-backs are crucial to that. Cedric Soares and Raphael Guerreiro whip in cross after cross in the hopes that an aerial threat like Cristiano Ronaldo can get a head on it. That's exactly what happened in the semi-final win over Wales.

Guerreiro in particular will have arguably his best challenge yet when he runs into right-back Bacary Sagna. Just as ambitious in the attacking third, Sagna will have to balance his contributions on both ends of the pitch if he wants to stymie his Portuguese counterpart.

Sagna's been one of the game's most consistent performers in the full-back position, and because France doesn't have true wingers, he's immensely important as an outlet and creator on the right side. Whereas Guerreiro more or less follows a straight line on the flank, Sagna is far more influential around his own box. In other words, the Frenchman's more difficult to track.

Cristiano Ronaldo vs. Laurent Koscielny

Good in the air in his own right, Laurent Koscielny has the unenviable task of detecting Ronaldo's late runs into the box. The Portugal captain has enjoyed a freer role under Santos, and although he excels on the counterattack, Ronaldo hasn't exactly had much of an opportunity to play that way. In fact, the Real Madrid superstar has played much deeper than he's used to. He's set up as many goals as he's scored in this tournament (3), meaning Ronaldo's spending more time outside the box.

Take a look at his starting positions in the semi-final against Wales. He's receiving passes on both the left and right sides of the pitch, allowing him to take space as he sees it and run into the box on an exclusive basis.

(Courtesy: Stats Zone)

Koscielny and partner Samuel Umtiti will have Nani to contend with as well, but Ronaldo's trickery and aerial ability will test them.

Antoine Griezmann vs. William Carvalho

After serving a suspension for yellow-card accumulation, Carvalho is expected to return to the lineup, and he will have to face the player of the tournament. Now in a central position, Griezmann has every chance to get behind Portugal's midfield and go one-on-one with Carvalho, who's mainly a cover for Pepe and Jose Fonte.

The 25-year-old Atletico Madrid forward can create opportunities for himself, and he's most dangerous around the top edge of the box. Carvalho has to make sure Griezmann doesn't find a way past him, but Pogba and Matuidi could also overload Carvalho.

The holding midfielder position is so crucial for Portugal because it allows the likes of Joao Mario, Renato Sanches, and Adrien Silva the opportunity to attack freely, meaning any mistake by Carvalho is that much more expensive.

The battle between Carvalho and Griezmann could determine the winner of this final.