Carlo Ancelotti felt Brazil were "anxious" in their World Cup opener against Morocco, as he suggested the pressure got to his players.

Brazil were largely underwhelming at New York New Jersey Stadium, as they opened their Group C campaign with a 1-1 draw.

World Cup 2022 semi-finalists Morocco made a fine start, which was capped off when Ismael Saibari charged through in the 21st minute and lofted a cute finish over Alisson.

With the unfit Neymar watching on from the bench, Vinicius Junior slammed home a brilliant equaliser 11 minutes later, but Brazil could not find a way through Morocco's defence for a second time.

In fact, Brazil relied on a sharp double save from Alisson late on to preserve a point, and Ancelotti knows there is plenty of scope for improvement.

"I think it was a tough match, especially in the first half," Ancelotti said, as reported by ESPN.

"Maybe the team was a bit anxious, and the nerves were all over the place. The second half was better, but it was still tough, and I'm sure we'll get better.

"I think that's something we'll have to look into.

"There's a lot of pressure, so it's natural. Little by little, we'll improve in that sense."

Brazil are, at least, unbeaten in their opening match in the last 21 World Cups dating back to 1938 (W17 D4).

It is the longest such streak in the history of the World Cup, more than twice as long as any other (Germany, Netherlands – nine straight).

Next up for the Selecao is Haiti, who lost their opener, going down 1-0 to Scotland.

"We have to reassess what we did," Ancelotti added.

"In the first half, we were very unbalanced. We did a bit better in the second half. The result isn't bad. You don't win the World Cup in your first match.

"I'm not disappointed, but I'm not satisfied, either. We need to work, but that's normal. Morocco played well. They're a solid team, very well organised. It was a difficult game.

"For many different reasons, a debut in the World Cup might not end up as expected. The goal is to qualify, move on to the next round and improve over time."

With uncertainty over how much Neymar will be able to contribute at this tournament, Brazil need Vinicius to step up, and the Real Madrid forward demonstrated his quality with a wonderful run and finish to restore parity.

It marked Vinicius' 10th goal for Brazil, with three of those coming on American soil.

"We started on a really bad note," Vinicius said. "For certain, we got to hold on to the ball. We have to move better."