Chile will press on against Brazil
In years to come, when the 2014 World Cup is remembered, most of the focus will fall on the knockout matches. What came before, Luis Suarez and open attacking play included, is all prelude. One fear, then, is that when the competition reaches the business end it might suddenly go cautious; as sapping conditions take their toll and the less ambitious teams seek to grind out their passage into the next round by taking the tie to a penalty shootout.
But there would seem to be little danger of caution playing much part in the first knockout match, the all-South American clash in Belo Horizonte between Brazil and Chile.
Jorge Sampaoli's Chile can only play one way: seeking to take the initiative, pressing the opponents in their half of the field, looking to create two against one situations down the flanks. With the space that Brazil leave behind their attacking full-backs, they could well have some joy.
Brazil, though, will consider themselves firm favourites. As Monday's 2-0 defeat to Holland made clear, the Chileans are vulnerable against set pieces and counterattacks, two areas of the game in which Brazil are very strong. If Chile's bold approach is not to prove suicidal, then, their defensive line will have to rise to the occasion.
This will not be easy. As Chile's captain and goalkeeper Claudio Bravo commented on the eve of the tournament: "We don't have a lot of defensive height. That's the way it was during qualification, and now we have to accept that risk again. We will have to use other resources to do well in the World Cup. But we've already played plenty of games with this formation, and we can take on any opponent on equal terms."
Bravo is Barcelona-bound precisely because he is so good at coming out and taking responsibility some 30 or 40 metres from goal -- ideal for a team that defend high, like the Catalan giants, and also, like Chile.
That lack of height at the back obliges Chile to place their defensive line high up the field. It also means that, like Barcelona, they can get away with having midfielders in their defence. One is Gary Medel, the little pit bull, who has spent most of his international career as a defender, snapping into tackles and distributing safely from deep.
Medel was teamed up with big centre-half Marcos Gonzalez, a Sampaoli favourite since they worked together with great success at the Universidad de Chile club. Gonzalez was then transferred to Flamengo of Brazil, who this year decided that he was surplus to requirements. At the age of 34, Gonzalez, they thought, was too slow. For a while he was kicking his heels, without a club. Sampaoli got him back training at Chile's complex in Santiago, but in the end concluded that he was short of match fitness and left him out of the World Cup squad.
In part this was because an experiment conducted in the friendly away to Germany in March had proved a success. Alarm bells were ringing when Gonzalez was inactive. Chilean football currently boasts very few centre-backs of both stature and quality. So Sampaoli tried another midfielder in his defensive line, the tall Osasuna player Francisco Silva. To the surprise of many in Chile, it worked well. Silva made sure of his place in the squad that night -- which has now become a place in the team.
It remains, though, a patch-up improvisation. Can it work against Neymar and co? If so, it will surely need a top performance from one of the great unsung heroes of the Chile side, central midfielder Marcelo Diaz.
Sitting in front of the defensive line, Diaz is the player who provides balance to the team. He has to position himself to protect those behind him, and with his range of passing he is the chief organiser of the early stages of the team's possession. Just as with Universidad de Chile, Diaz is an extension of coach Sampaoli on the field, only with a little more hair.
Tim Vickery is an English journalist who has been based in Brazil for the past 20 years. He is the South American football correspondent for the BBC Sport.