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1. The two sides of Brazil

We saw two Brazils in the World Cup opener against Croatia. There's the flair side, with Neymar and Oscar making things happen. And then there's the side that looks really vulnerable in defence, and beatable.

Paulinho and Luiz Gustavo didn't protect the back four enough. The two full-backs, Dani Alves and Marcelo, were bombing forward with no concern for what was behind.

And as for David Luiz, how on earth is he worth £50 million?

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We all know Brazil are great going forward, but against a really top-quality side I think they could be punished for those defensive weaknesses.

2. Samba Sao Paulo

I arrived on Wednesday in Sao Paulo. There are 20 million people in the city and it felt like everything came to a standstill as the game approached on Thursday.

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The atmosphere at the stadium was amazing—quite incredible noise and the anthem was so emotionally charged. The Brazilian public have been waiting for their moment for so long, and they celebrated Thursday.

There's still a sense of looming discontent, however. We saw police blocking off roads to the stadium to allow safe passage to journalists. Everybody wants Brazil to do well, but at the same time there's the frustration with infrastructure and a lot of political discord.

3. Shocker: Yuichi Nishimura

Brazil striker Fred intentionally backed into Dejan Lovren and tried his luck. He went to ground too easily, and the referee made the wrong decision.

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You might also argue he could have sent Neymar off for an elbow on Luka Modric, so it wasn't a great day for Yuichi Nishimura.

4. Italy bonus for England

Mattia De Sciglio's injury is potentially good news for England. It could mean Giorgio Chiellini has to play as a full-back for Italy, which could make for an unsettled back four.

Might Roy Hodgson take that lead and play Raheem Sterling? The consensus among the media pack is that Hodgson will stick with Danny Welbeck, but you never know.

It does seem the England camp are in very good spirits. Everything has gone smoothly so far, but the real test comes on Saturday—in 100-degree heat and the humidity they'll face in the Amazonia Arena.

Until then.