PADERBORN, Germany -- It didn't take long for defender William Saliba to pick his favourite photo from Friday's quarterfinal between France and Portugal.

Of course, he loved Theo Hernández's winning penalty in the shootout, the celebrations that followed with the France players, and the communion with their delirious fans inside the stadium in Hamburg. But the one moment, the one snapshot he chose, was when he fended off Cristiano Ronaldo's challenge after getting the ball off him in the first half. It's true Ronaldo, 39, is not the player he used to be, but he's still one of the game's greatest and in Saliba's first encounter against him, the Arsenal centre-back showed his class.

Saliba is having a wonderful Euro 2024. He is arguably the best defender left in the competition -- France face Spain in the first semifinal on Tuesday, with England and Netherlands doing battle 24 hours later -- and, having been the best in the Premier League last season, might just be the best defender in the world right now.

A month ago, Saliba walked into Clairefontaine (the France national team's HQ in the south of Paris) as a substitute. In Didier Deschamps' mind at the time, Dayot Upamecano and Ibrahima Konaté were his two starters at centre-back, just like they were at the 2022 World Cup. When it came to Saliba, the head coach still had some reservations ... much like the ones he'd expressed in March, when he said he didn't consider him ready to start for France.

Deschamps felt the 23-year-old could be more focused and show more ruthlessness in one-vs.-one situations. Saliba didn't take it personally; the two had a long discussion during the pre-Euro camp and, at the end of it, the Paris-born defender felt he could change his coach's mind. And he has done just that.

The most impressive thing with Saliba is his quiet ambition and motivation to prove people wrong. He did it at Arsenal with Mikel Arteta, who was not at all convinced initially about the defender's role in his team and was sent out on loan. He did it with Jorge Sampaoli at Marseille. And he's done it this summer with Deschamps.

It's important to bring some perspective to just how good Saliba has been for France: he had never started a single game at a major tournament until he faced Austria three weeks ago. Yet he has shown so much confidence, calmness and power -- and against the likes of Marko Arnautovic (Austria), Memphis Depay (Netherlands), Robert Lewandowski (Poland), Romelu Lukaku (Belgium) and, of course, Ronaldo as well. None of these world-class forwards have managed to dribble past him once or to cause him problems.

Saliba's partnership with Upamecano, and with Mike Maignan in goal behind them, has been amazing to watch and they've built a strong understanding. As soon as the game against Belgium finished, the two defenders hugged, then ran towards their goalkeeper for a group embrace. In that round-of-16 game, Saliba came up against Lukaku in the first real blockbuster "striker vs. defender" duel of the tournament and the Frenchman won it easily as Les Bleus advanced 1-0.

Having made the journey from squad player to starter, it's fair to say Saliba is now France's most important player -- more than Kylian Mbappé or Antoine Griezmann, the two stars of this squad.

Right now, the debate in France is focused on whether the latter pair should even keep their place in the starting XI for Tuesday's semifinal against Spain in Munich. That Mbappé is clearly out of form and having to wear a protective face mask (after suffering a broken nose earlier in the tournament) is a big problem. But he is the captain and the best player in the world, even if he hasn't showed it here in Germany yet, so it's likely he plays.

Griezmann is a different story. At 33 -- and despite Deschamps' trust, love and willingness to try and fit him into the team by changing the tactical system around him -- it looks like his legs and creativity simply aren't there this summer. He has scored just two goals in his last 33 caps, and doesn't have the same X-Factor as he did before.

Facing Spain will be a special game for Atlético Madrid's Griezmann, considering his relationship with a country where he has lived and played longer than he did in France. His defensive work behind the ball and in the press is still very much appreciated by Deschamps, but is that enough for him to keep his place in the XI? Ousmane Dembélé was outstanding when he came on to replace him against Portugal just after the hour mark.

When Dembélé walked into the dressing room with his "Player of the Match" trophy after the game, the chants of "MVP, MVP, MVP" grew louder as the song "MD" by Tiakola and Niska (two rappers from Paris) blared from the speakers. It will be hard to put him on the bench again after that performance.

The belief within this group is rock-solid and their confidence of winning Euro 2024 now is strong. But the games and sense of fun within the camp has been key in keeping the pressure off ahead of the semifinal against tournament-favourites Spain. For a long time, Saliba was unbeaten at Uno, but Dembélé has since taken his crown! (By the way, N'Golo Kanté is still very much suspected of cheating, like Upamecano.) On the PlayStation, Mbappé has been invincible on NBA 2K -- although Griezmann has given him some good games.

Spain are familiar foes and several of France's players (Hernandez, Jules Koundé, Aurélien Tchouaméni, Eduardo Camavinga and Dembélé, to name a few) know their opponents well from playing in LaLiga for Real Madrid and Barcelona.

In 1984 and in 2000, Les Bleus beat Spain en route to winning their two European Championships. If these trends always come in threes, 2024 could yield the same outcome.