Since the advent of the internet, coaches have found it far easier to do their homework and prepare for matches against unfamiliar teams featuring unknown players. Such research is essential in the build-up to competitions like the FIFA U-17 World Cup Mexico 2011, and the benefits of it were clear to see on the opening day in Group F, where Australia’s in-depth knowledge of opponents Côte d’Ivoire was a factor in their 2-1 win.

In contrast, Monday’s other game in the section, between Brazil and Denmark, provided an example of what can happen when an opposing player slips under the radar. Unaware of the attributes of Ademilson, a late addition to Emerson Avila’s squad, the Scandinavians were powerless to prevent him from scoring twice in a 3-0 defeat and from setting up his side’s other goal.

The Sao Paulo player was an absentee from the Brazil side that won the South American U-17 Championship in Ecuador in March - an omission that caused an unexpected problem for Thomas Frank. The Denmark coach had studied the Brazilians closely at that tournament, but with Ademilson nowhere to be seen, he was unprepared for the player's impact in Guadalajara, as he later admitted to

“It was a big surprise,” Frank said. “We would have liked to have had some DVDs of him. He was the key player out there and when he scored his first I thought to myself, ‘OK’. The second was a much better goal, which he finished very well. He was quick and he showed a lot of skill too.”

Opposite number Avila was not entirely pleased with A Seleçãozinha’s performances in the continental championship, believing there was room for improvement despite winning the title again. Looking to strengthen the coach’s hand, the Brazilian Football Federation (CBF) sent their nationwide army of scouts to work, while Avila took the unusual step of asking some of his trusted charges to suggest some possible reinforcements. Among that group was the highly rated Lucas Piazon, and the name he came up with was his Sao Paulo team-mate Ademilson.

You have to keep a sense of perspective but there are times when he reminds you of Romario, with his speed and quick passes, and he’s a great finisher too.

Emerson Avila on Ademilson

Discovered by the Morumbi club playing for a team in the nearby area of Baixada Santista, part of its network of youth academies, Ademilson admitted to being surprised at his first national team call-up despite a fine Sao Paulo state campaign with O Tricolor:

“I’d always hoped to play in a championship but I never expected to get the call for a World Cup," he said. "When I heard I was in the squad I knew it was my opportunity, that I had to give my all.”

And give his all he did, impressing so much at Brazil’s pre-tournament training camp that he had made the No9 shirt his own by the time the team reached Mexico, tightening his grip on it with that stunning show against Denmark. “I gained Emerson’s trust little by little, and thank God he gave me a starting place,” said the two-goal hero. “It went well for me and now I have to keep it up.”

The Brazil coach has even seen fit to liken Ademilson to one of the greatest centre-forwards the country has ever produced: “You have to keep a sense of perspective but there are times when he reminds you of Romario, with his speed and quick passes, and he’s a great finisher too.”

As much as he rates him, even Avila was not expecting such a return from his young striker on his debut: “Considering it was his first game in a Brazil shirt he surprised us too."

One can only imagine, then, how taken aback the Danish defenders were after 32 minutes of Monday’s game, when Ademilson collected the ball from well outside the box and fired his side into the lead from distance. With Frank later admitting that he was more concerned with Piazon, the unknown quantity had the space he needed to create mayhem.

“They were getting tighter on Adryan and Piazon, who both went to the South American Championship and played well there,” explained Ademilson. “That gave me a little more space and the rest was up to me. Things should be tougher in the second game, though. I should have a least one marking me then, and maybe even two or three.”

That second game is against the Australia tomorrow. And if Ademilson causes the same kind of mischief again, the Aussies cannot claim they did not see it coming.