The under-23 team, which had been touted as a medal favourite, left Glasgow for London to join up with the rest of Spain's Olympic athletes after losing 1-0 at Hampden Park on Thursday. The result threatens the country's attempt to simultaneously hold the World Cup, European Championship and Olympic titles.
Midfielder Oriol Romeu admitted the team is irritated by the defeat, but is confident the players will bounce back for Spain's next Group D match against the Hondurans on Sunday in Newcastle.
"It will do us good to rest and return to our best, so we can beat Honduras," Romeu said. "We more than anyone believe in ourselves."
If the Olympic side has any hope of winning a medal, it will have to try to repeat the national team's record at the 2010 World Cup, when the senior players lost their first match in the group stage, but went on to win the tournament.
"I have tried to be positive in the dressing room, because we have two more opportunities," coach Luis Milla said. "We have to improve things. We don't have much time to work on them and it will have to be a lot of work on the mental side, on concentration."
After the Honduras match, Spain's last group match is against Morocco on Aug. 1 in Manchester. Both of Spain's remaining group opponents showed in their own match Thursday, which ended in a 2-2 draw, that they will not roll over easily.
But goalkeeper David de Gea is confident Spain will rise to the challenge.
"At times, you take a hit and you have to get up," de Gea said. "Two matches remain, which are two finals, and we have to win them. We have the example of the national team, which started off their World Cup campaign by losing, and look — they're world champions."
For the match against Japan, Spain was missing one of its most creative players. Forward Iker Muniain has been sidelined because of a right leg injury, but Spain is hopeful he will be fit for the match against Honduras. Center back Inigo Martinez was sent off in Thursday's match and will be suspended Sunday.
There has been immense pressure in Spain for the Olympic football team to come back with gold to add to its already cluttered trophy cabinet. Spain also holds the European under-19 title.
Milla, however, doesn't believe his players crumbled under the weight of the high expectations.
"We have taken up the responsibility," he said. "Those of us who are part of Spanish football are happy about our successes. We aware of it (the expectations), but now we're thinking about the match against Honduras."
After Thursday's defeat, questions were raised about whether it was a good idea for the players to fly to London for the opening ceremony when so much tune-up work needs to be done before the match. The team will then have to fly back north again to Newcastle.
"It was planned regardless of the result (of Thursday's match) and it won't change anything," Milla said. "We thought it was best for the harmony of the group. We should enjoy the moment, but also think about the 'final' against Honduras."
Romeu exuded confidence about Spain's chances of making a comeback in the tournament, believing the rest day will be a good thing for the team.
"We'll rest a bit and will return to work with eagerness ... so we can win the next two matches and give our all," he said. "We're still alive (in this tournament) and have a lot to say."