Al Khor,  Ecuador manager Gustavo Alfaro said he was happy but not "totally satisfied" with his team's 2-0 victory over hosts Qatar in their opening match of the 2022 FIFA World Cup on Sunday.

"The most important thing today was to win. I'm not totally satisfied because we know there are a lot of things we can improve, but we are all learning, including me," the Argentine coach told a post-match press conference at the Al Bayt Stadium.

"It's a great victory. All games in the World Cup are difficult but the opening match against the tournament hosts involves more tension. We didn't know how our level would be because there was little time to prepare. We only had four days to get ready for this game. Added to that was the fact it was the opening match of the World Cup, and this is a young team," he was quoted as saying by Xinhua.

Alfaro said his players needed to raise their game to another level in their remaining group-stage matches against Senegal and the Netherlands.

"Today we took an important step but it's not decisive. There are teams that have won their first match of the World Cup and not advanced (to the knockout stage). But having said all of that, this victory is important and it will give us confidence.

"We were good in this match but we shouldn't get ahead of ourselves. We are in a period of construction. We know that what we achieved in the (South America zone) qualifiers isn't enough. Here we are up against the best teams in the world. The times are short between each game."

Playing in their fourth World Cup, Ecuador's best ever finish in the tournament was a round of 16 appearance against England in 2006, which they lost after a trademark David Beckham free-kick.

"We have big hopes but it's hard to say how much we can advance in the tournament. It will depend on how much we are able to improve and incorporate aspects to our game that we need to get better," Alfaro added.

Meanwhile, Qatar manager Felix Sanchez admitted his team suffered from an attack of nerves during their 2-0 defeat to Ecuador.

Fenerbahce forward Enner Valencia scored two first-half goals as World Cup debutants Qatar became the first host team to lose the opening match of football's showpiece tournament.

"Nerves got the better of us," Sanchez told a post-match press conference. "We competed well but it's a World Cup and we were playing in it for the first time. In front of our fans we weren't able to be at the level we would have liked after a bad start."

Sanchez vowed he and his backroom staff would analyze what went wrong and make any necessary changes ahead of their next match against Senegal on Friday.

"It wasn't the game we'd hoped for," he said. "We have to analyze the match and try to prepare for the next one, which will be as tough or even tougher than this one. We will look at how we can be more effective with the players we have available."

"We have to congratulate our opponents. They were deserving winners. We can improve a lot and we know we haven't shown our maximum level. Nerves got the better of us early. We started badly and that hurt us. We have to handle the pressure better and be more competitive in our next matches."

The Spaniard, who has been Qatar's manager since 2017, added: "We lacked precision at key moments and we weren't able to string more than four passes together.

"We were also poor in transitions. When you play at this level if you make a mistake you get punished. We will try to be stronger and more compact in our next match. We know that we have to move the ball faster and pass the ball better to be effective against teams in this competition."