Other Spanish players in Qatar who played at the Olympics are striker Marco Asensio, midfielders Pedri and Dani Olmo, and goalkeeper Unai Simon.
After Japan stunned Germany 2-1 in their opening match they made many changes to their side and lost 1-0 to Costa Rica, who had been thrashed by Spain 7-0 in their opener.
Torres suggested the side may have let their opening win go to their heads.
“Maybe it was overconfidence, having won the first game, as well as having seen our result against Costa Rica,” the defender, who plays for Spanish LaLiga side Villareal, said.
“We made that match look easy and then we could see that after all, it wasn't easy at all.”
Spain could have booked their last 16 spot already but drew their second match, against Germany, meaning it comes down to match number three.
“Against Germany we knew they could challenge us for possession. We played in a similar way,” Torres said.
“We are perhaps a little more organised when it comes to pressing and we took the lead. After that goal they started to accumulate more people in attack and I think it was a fair draw.”
Spain's youngsters to draw on Olympics experience for Japan clash
Spain may look to their younger players to seal their last 16 spot at the World Cup when they meet Japan on Wednesday and some of those players, including defender Pau Torres, will draw on their Tokyo Olympics experience to help them prepare.
Some of Spain's under-23 squad from Tokyo are in Qatar and remember their semi-final clash with Japan.
Spain won 1-0 and eventually took the silver medal, while Japan lost out in the bronze medal match.
“In the semi-final we needed to go all the way to extra time to win,” Torres, who played all six of Spain's games in Tokyo, told Reuters on Tuesday.
The two sides also drew in a friendly before the Games.
“Japan are an organised team, consistent in what they do. I always think they have the game under control, they don't get out of the game until the final minutes.
“And they are comfortable defending without the ball. They don't need to feel they have possession to be comfortable. It's going to be a tough game.”
Other Spanish players in Qatar who played at the Olympics are striker Marco Asensio, midfielders Pedri and Dani Olmo, and goalkeeper Unai Simon.
After Japan stunned Germany 2-1 in their opening match they made many changes to their side and lost 1-0 to Costa Rica, who had been thrashed by Spain 7-0 in their opener.
Torres suggested the side may have let their opening win go to their heads.
“Maybe it was overconfidence, having won the first game, as well as having seen our result against Costa Rica,” the defender, who plays for Spanish LaLiga side Villareal, said.
“We made that match look easy and then we could see that after all, it wasn't easy at all.”
Spain could have booked their last 16 spot already but drew their second match, against Germany, meaning it comes down to match number three.
“Against Germany we knew they could challenge us for possession. We played in a similar way,” Torres said.
“We are perhaps a little more organised when it comes to pressing and we took the lead. After that goal they started to accumulate more people in attack and I think it was a fair draw.”
After Spain's opener, coach Luis Enrique said he would rotate his young squad because “he was not going to play with the same line-up for seven games”.
Asked what the key message was in the coach's statement, Torres — who has yet to play in Qatar, his first World Cup — was clear.
“That we're going to go all the way to the final, right?” he said with a smile. “Hopefully, whoever plays we'll get to play all seven of them. It will mean we are doing very well.
“I think we can compete against anyone.”
Between tournament duties, the young Spanish players have been soaking up the experience, and not only on the pitch.
“We were lucky that there were four different schedules throughout the day,” Torres said.
“If we trained in the morning we could watch the midday and afternoon games. We have a room where we can get together, with a big screen to watch the football and there are always several teammates there.
“Germany's defeat against Japan, Argentina's one against Saudi Arabia show the level in this World Cup is high. No matter which team you play you always have to be prepared for everything.”
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