Great Britain coach Stuart Pearce said his team were inspired by other GB competitors after they defeated Uruguay in Cardiff to reach the quarter-finals.
The 1-0 victory came after GB struck gold in rowing and Bradley Wiggins triumphed in cycling's time trial.
"The feel-good factor is spreading and we are delighted to play our part by getting out of the group," said Pearce.
"I have also got to mention the women's team defeating Brazil on Tuesday, it gave us a good lift."
Daniel Sturridge scored the only goal at a passionate and atmospheric Millennium Stadium as GB eliminated Uruguay to finish top of Group A and set up a quarter-final tie against South Korea at the same venue on Saturday.
Pearce added: "It excites me to stay in the competition for at least one more match because we have improved game by game, the fitness levels are improving, as is the understanding.
"I am delighted to be out of the group, looking back you can see how tough it was, but I think over three matches we deserved to come top, the team has got stronger and stronger.
"Now it is about recovery and preparing for Saturday. My feet are on the floor and [I'm aware of] the magnitude of the next game in front of us."
South Korea finished second behind Mexico in Group B after two goalless draws and a victory over Switzerland.
"I watched South Korea when they beat Senegal 3-1 in a friendly at Stevenage," stated Pearce.
"They are a hard working side. We did not know who we would be playing in the quarter-finals if we got through but we have had scouts at every game and we have footage of them playing."
Pearce was candid about his team's medal prospects now they are one win away from guaranteeing a bronze medal match at the very least.
"We have only ever planned and prepared to win the tournament," said the GB coach.
"The coaches of all the teams in the last eight know they will have two shots at getting a medal if they get to the semis.
"Because even if you are unsuccessful in the semi-finals you get the shot at the bronze, so the importance of this next game is very high."
Wednesday's match was played in front of more than 70,000 in the Millennium Stadium - and the passionate crowd generated a superb atmosphere as GB held on against a Uruguay team desperate to extend their Olympic campaign but are now heading home.
"When I look back three or four weeks people were telling me there would be a negative response in Cardiff but I have not seen that," added Pearce.