Two hours in, the restaurant carriage of the 1.52am sleeper train from Moscow to St Petersburg is bouncing. As the lakelands of central Russia pass by the windows, enhanced by the glow of northern midnight sun, two sets of supporters have formed an unlikely musical bond.

The Brazilians are following locals in singing the classic Russian terrace chants – Ross-i-ya, and Vperyod Rossiya [Go Russia!], but adding the swagger of their own bossa nova rhythms. And the Russians are clapping deliriously as the Brazilians recite their most recent hit, E o argentino está chorando. Messi tchau tchau tchau [The Argentine is crying, bye bye Messi].

There must be fifty fans in the carriage, and it’s standing room only. Some of the Brazilians are sitting barefooted and bare-chested atop the benches, their arms and beer cans outstretched. None of the outlandishness seems to bother the middle-aged waitresses, who scuttle through the carriage with permanent smiles on their faces. The two policemen on duty look on, occasionally sniggering to each other.

These are not normal scenes for Russia. Had this been a regular train, the mere sight of bare feet on the leather seats would have had consequences. Then again, these are not normal times. Russia has waited many years for its World Cup party, and it won’t let its own bureaucracy get in the way of the carnival.

Few observers have failed to notice the absolute revolution in Russian policing. The Kremlin has populated its front line with fresh-faced twenty-somethings, straight out of police academy and the first people foreigners will see. And even the experienced back-up, comprised of battle-scarred OMON riot police, have been seen cracking a smile.

But the old Russia is never far away.

A few days ago, at the time a Swedish fans took over Nizhny Novgorod, Russia’s fifth city, two local activists faced trial. The sentencing was not widely reported, but few surprises were expected. Both were convicted. One pro-Ukrainian activist was given a custodial sentence. The other was given a large fine. His crime was taking part an “unsanctioned” march in memory of Boris Nemtsov, the opposition leader murdered three years ago.

The irony of the Swedish invasion of Nizhny was that thousands of fans would later occupy the main city thoroughfare. It was an unsanctioned march in all but name.

Russians can see through that and many of the tricks being used by authorities, says the sociologist Alexandra Arkhipova. Most understand how the Kremlin have used the tournament to bury bad news such as raising the pension age, increasing VAT, and placing new pressures on independent universities.

“People don’t like such deception, or the idea of building Potemkin villages to show off in front of foreigners,” she says.

But little of that is likely to dent Russian enthusiasm for the tournament itself. Not only has the national team outperformed all expectations, but major Russian cities have also turned into melting pots of new and exciting cultures like never before.

“Some of us are beginning to see ourselves as part of a bigger world,” says Ms Arkhipova. “Positive social change can come out of this.”

In St Petersburg on Friday, as Brazilian fans celebrated an injury-time 2-0 win over Costa Rica, locals queued up to be photographed with the most outrageous of the costumes. They posed with mohawks, fluorescent wigs, gypsies, Mexican wrestling masks and cross-dressers. Some of them joined in chanting, dancing and beer drinking.

Brazil vs Costa Rica World Cup player ratings Show all 22 1 /22 Brazil vs Costa Rica World Cup player ratings Brazil vs Costa Rica World Cup player ratings <b>Brazil:</b> Alisson - 5 out of 10 Rarely called upon, the in-demand Roma goalkeeper did not have to save a single shot on target. Getty Brazil vs Costa Rica World Cup player ratings Fagner - 5 out of 10 Brazil's third choice right-back was fine in defence but offered little support to Willian and Costa. Getty Brazil vs Costa Rica World Cup player ratings Thiago Silva - 6 out of 10 A quiet afternoon for the captain, who showed composure in sweeping up some rare Costa Rica attacks. Getty Brazil vs Costa Rica World Cup player ratings Miranda - 6 out of 10 Busy against the Swiss, less so in Saint Petersburg. He tracked Ruiz admirably when the Costa Rican threatened to impose himself. Getty Brazil vs Costa Rica World Cup player ratings Marcelo - 7 out of 10 An energetic presence down the left flack, he supplied the cross that led to Brazil's late opener. Getty Brazil vs Costa Rica World Cup player ratings Paulinho - 7 out of 10 The Barcelona midfielder impressed during his 68 minutes and could have won a legitimate penalty in the first half when pulled over in the box. Getty Brazil vs Costa Rica World Cup player ratings Casemiro - 6 out of 10 Recovered from an early nosebleed to battle box to box. He passed up a free header to open the scoring in the second half. Getty Brazil vs Costa Rica World Cup player ratings Philippe Coutinho - 8 out of 10 Continues to prove himself Brazil's most important player. Was off target with some long range efforts but in the right place to score a crucial goal at the death. Getty Brazil vs Costa Rica World Cup player ratings Willian - 4 out of 10 A disappointing first half of miscued crosses saw him subbed at the break. Getty Brazil vs Costa Rica World Cup player ratings Gabriel Jesus - 6 out of 10 Not his best afternoon. He netted an offside goal, hit the crossbar with a header and set up Coutinho with a poor first touch. Getty Brazil vs Costa Rica World Cup player ratings Neymar - 5 out of 10 His flashes of brilliance were outweighed by the cheating, petulance and poor misses. By the time he scored, he had lost a lot of admirers. Getty Brazil vs Costa Rica World Cup player ratings <b>Costa Rica:</b> Keylor Navas - 8 out of 10 Made save after save to keep Brazil out. Did not deserve to end up on the losing side. Getty Brazil vs Costa Rica World Cup player ratings Johnny Costa - 7 out of 10 Defended by any means necessary to repel the threat of Neymar and Jesus. Getty Brazil vs Costa Rica World Cup player ratings Giancarlo Gonzalez - 6 out of 10 Another who stood up to Brazil's attacking threat although VAR came to his rescue after he was incorrectly adjudged to have fouled Neymar. Getty Brazil vs Costa Rica World Cup player ratings Oscar Duarte - 6 out of 10 A physical presence in defence, although sometimes too physical. Was fortunate to get away with his challenge on Paulinho in the box. Getty Brazil vs Costa Rica World Cup player ratings Cristian Gamboa - 7 out of 10 Impressed down the right especially in the first half. He attacked at pace and often kept Neymar under wraps. Getty Brazil vs Costa Rica World Cup player ratings Celso Borges - 6 out of 10 Always a willing runner, he passed up Costa Rica's best chance in the first half with a sidefoot wide. Getty Brazil vs Costa Rica World Cup player ratings David Guzman - 6 out of 10 Stemmed the Brazil tide for long periods, he found himself overrun when the tempo was upped. Getty Brazil vs Costa Rica World Cup player ratings Bryan Oviedo - 6 out of 10 The Sunderland man came into the Costa Rica side and performed well, producing one tremendous defensive header to deny Jesus. Getty Brazil vs Costa Rica World Cup player ratings Johan Venegas - 4 out of 10 Apart from a couple of nice links with Gamboa, he failed to make an impact on the game. Getty Brazil vs Costa Rica World Cup player ratings Bryan Ruiz - 6 out of 10 The captain showed some neat touches, but too often was forced to drop deep to influence proceedings. Getty Brazil vs Costa Rica World Cup player ratings Marco Urena - 5 out of 10 Still struggling for fitness, he mistimed a number of runs before being replaced. Getty

Marina Yermokova, 41, from Bashkortostan, said she had travelled 2,000km to be in Russia’s second capital for the tournament. Things in St Petersburg had become a “touch chaotic” since the foreigners arrived, she admitted, but the “wonderful” scenes on the streets made up for it.

Her friend, Tatyana, 40, said, rather more sternly, that Russians understood all changes were temporary, “normality would return in three weeks’ time”, she added. “Of course, we’ll go back to the way things were, but in the meantime we will enjoy ourselves.”

Many of the Brazilian fans said it wasn’t difficult to understand how different they were.

“Yeah, the stares – it’s like you are from a zoo, another planet,” said Thiago Vitale, 39, a journalist from Brasilia. “The Russians are good people, but perhaps they need to loosen up, smile a bit more.”