Brazil men's Olympic football team captain Neymar said that Thursday's 0-0 opening day draw against 10-man South Africa felt "like a defeat."

The host nation are huge favourites to take the gold medal at this summer's Olympics in Rio de Janeiro and feature other big names such as Manchester City's new £27 million signing Gabriel Jesus and Paris Saint-Germain centre-back Marquinhos, but Rogerio Micale's side were unable to find a goal even after Mothobi Mvala's sending-off early in the second half.

Speaking to Globoesporte after the game in Brasilia, Neymar admitted that nerves had played a part in the poor showing by his side, but said he was confident they would do better in Sunday's second Group A game against Iraq.

"The first game is always the most difficult, for the nerves you have before you begin to play," he said. "For us, the draw is like a defeat. We have to win, we know our responsibility. We will stay calm and get back to work again as soon as possible so that we play well on Sunday."

Brazil come into the tournament under huge pressure, especially after the disappointment of the 2014 World Cup, when the hosts were embarrassed 7-1 by Germany in the semifinals.

Neymar pointed out that no Brazil team has won an Olympic title, even with emerging stars including Romario, Ronaldo, Rivaldo, Roberto Carlos, Bebeto and Ronaldinho each taking part in at least one tournament.

"I don't know how many great Brazilians have played in the Olympics and not been able to win it," he said. "We know this is not easy, we cannot just show up and take home the gold medal. We must play our football. We found it more difficult [tonight], and we must learn to overcome this."

Against South Africa on Thursday, Jesus had an excellent chance to score midway through the second half, but hit the post from just 3 yards out. He told Globoesporte he said he was embarrassed at having missed such a simple chance and would find it hard to forget the moment.

"I had to score that goal," he said. "I could not miss it. I'm very upset, I'm not going to sleep tonight. I keep thinking about it, watching it again and again. It's embarrassing."