The poster boy of this World Cup came into the tournament with the responsibility of delivering Brazil the trophy they prize above all else.

At the Arena de Sao Paulo, he stepped up to the mark, finding the net either side of half-time to bring Brazil back from the brink after Marcelo had scored an early own goal.

Oscar cemented the result with a wonderful individual goal late on but the adulation went to the man with the No.10 on his back.

Neymar's first goal was a low, sweeping effort that crept into the net from 25 yards. His second, 19 minutes before the end, was altogether more controversial.

Dejan Lovren was adjudged to have fouled Fred in the box and Japanese referee Yuichi Nishimura pointed to the spot, despite replays showing little contact had been made. Neymar converted to spark scenes of celebration.

It ensured a 10th consecutive win for Luiz Felipe Scolari's side but Brazil did not play with the fluency or flamboyance that saw them swat aside Spain to win the Confederations Cup so emphatically last year.

Their performance demonstrated flaws and fragilities but they will become harder and harder to beat.

The moments before kick-off had been typically rousing. A passionate Brazilian crowd delivered another fervent rendition of the national anthem. Croatia were no more than an afterthought to most outside the thousand travelling fans.

That soon changed. From the off, Ivica Olic worked tirelessly, chasing lost causes, committing Brazilian defenders. He might have scored after seven minutes only to head Ivan Perisic's right-wing cross narrowly wide at the back post.

Four minutes later he was at the heart of the move that stunned Arena de Sao Paulo into silence.

With Dani Alves committed upfield, Olic found space wide on the left. His low, teasing cross found Nikica Jelavic who made glancing contact, but it was enough to catch Marcelo off balance and the Real Madrid defender watched on horror as the ball deflected off his ankle and rolled into the net beyond goalkeeper Julio Cesar.

Brazil were struggling for rhythm; insipid not inventive. They needed a moment of magic, a spark. It would come from a familiar source of inspiration.

All eyes had been on Neymar da Silva Santos Junior before kick off. The fresh-faced boy with the weight of a nation on his back had been splashed across every newspaper in Brazil, featured on every TV station and his name had been uttered by every fan.

When his team-mates needed him most he did not disappoint. He was, though, fortunate to escape a nasty first-half incident - when he caught Luka Modric in the face with a swinging forearm - with only a booking.

The incident helped Brazil find a spark. Oscar tested Croatia goalkeeper Stipe Pletikosa with a shot that fizzed and curled fiercely. Two minutes later, the Chelsea midfielder was in the thick of it once again, fighting through two challenges and finding Neymar.

When the Brazil No 10 turned for goal, moving the ball on to his left foot, he had one thing in mind. The contact was not pure but the shot was unerringly accurate, creeping in from 25 yards, glancing the right post on its way.

The celebrations on the touchline told a story. Scolari was swamped by his players as all 23 Brazilian squad members rejoiced in the overwhelming sense of relief. Fireworks echoed in the streets around the ground. A weight had been lifted, a fear allayed.

Croatia, though, were far from finished. Dejan Lovren provided solidity and strength in defence; Ivan Rakitic, the spark and substance in midfield.

For long periods, Brazil struggled to find the zip in their passing, or the vim and vigour in their movement, to elude markers and dismantle Croatia's effective and organised defensive system.

Dani Alves curled a dipping free-kick just over but that was the sum of Brazil's second-half efforts as the final 30 minutes approached. That was to change.

Oscar broke down the right and crossed for Fred, who went to ground under the challenge of Lovren. The referee pointed to the penalty spot. Neymar fired in the resulting spot kick, the ball deflecting in off the out-stretched arm of Pletikosa.

It was harsh on Croatia, with replays showing minimal contact. Brazil did not care.

Oscar put a gloss on the final score with a tremendous late goal that his man-of-the-match performance warranted. With Croatia committed upfield, he burst forward and toe-poked in from 25 yards, taking Pletikosa by surprise with a fierce low drive.

Brazil are off and running. They make take some stopping.