Update: 11:54AM World Cup host and favourite Brazil was held to a 0-0 draw by Mexico on Wednesday morning in an absorbing Group A match in the deafening cauldron of Fortaleza's Castelao arena.
Brazil failed time and again to break down a stubborn defence backed up by inspired goalkeeper Guillermo Ochoa but the Mexicans also created several decent chances in another entertaining game.
Paulinho and Neymar came close to finding the back of the net but were thwarted by Ochoa who also parried Thiago Silva's point-blank header in the dying minutes.
"It was a very difficult match," Ochoa told reporters.
"We knew it would be tough for Brazil because they're playing in their country. We knew we would have to be focused 100 per cent for all the 90 minutes."
The draw brought to an end Brazil's 10-match winning streak, dating back to August.
"There was a chance here, a chance there, it was very tight," Brazil coach Luiz Felipe Scolari said.
"It wasn't a question of us evolving or not (from the last game). We've been playing this way 20 games, we are up against good teams, we need to understand that.
"It wasn't a good result, a victory would have qualified us. We need to respect other teams."
To make sure of reaching the second round of the tournament both teams need points from their final group games on June 23 when Brazil face Cameroon in Brasilia and Mexico meet Croatia in Recife.
Brazil bossed the match from the outset with Marcelo and Oscar causing mischief down the left and Neymar showing the occasional burst of brilliance in the middle.
Neymar's header from a Dani Alves free kick on 26 minutes forced the first fine save from Ochoa, who beat the ball away at his right hand post as it headed goalwards.
Brazil's best chance of the half came just before the break. Oscar floated a free kick into the box, Thiago Silva chested it down into the path of Paulinho, who just failed to scoop the ball over the keeper from close range.
At the other end, Mexico were restricted to long-range efforts from Miguel Layun, Jose Vasquez and Hector Herrera, none of which seriously troubled Julio Cesar in the Brazilian goal.
This was the first time that Mexico had held Brazil to a draw at a World Cup. Their previous three clashes ended in comprehensive victories for the Brazilians, 5-0, 4-0 and 2-0.