1150 BST: The final whistle sounds and the American bench charge onto the field to embrace the players who have achieved their country's greatest World Cup result since they beat England in 1950.
Full-time: USA 3-2 Portugal
90 mins (+2): DaMarcus Beasley is booked for time-wasting.
90 mins (+1): The USA win a corner which Portugal clear but time is now running out for Antonio Oliviera's side.
90 mins: Sergio Conceicao is down with cramp as Cobi Jones heads for the corner, where he draws a rash foul from Paolo Bento.
89 mins: The USA manage to take play downfield and Cobi Jones runs down the clock by the corner flag.
87 mins: The Americans mount a now rare raid into Portuguese territory but Vitor Baia easily saves Joe-Max Moore's weak shot from the edge of the box.
86 mins: The USA cannot retain possession but are prepared to defend desperately to preserve their lead.
84 mins: The Portuguese look to be running out of ideas and Joao Pinto hits a hopeful long-range shot tamely wide.
82 mins: Portugal strive for a late equaliser but are still not playing with real fluency. Pauleta carves out another opening for them, but loops his cross onto the roof of Brad Friedel's net.
79 mins: Both teams make further substitutions, with Nuno Gomes replacing Rui Costa to give Portugal another man in attack, and Carlos Llamosa coming on in place of Eddie Pope for the USA.
77 mins: The USA are living increasingly dangerously and Pauleta creates more danger for them when he chips the ball back across goal from Luis Figo's free-kick, but just beyond his stretching team-mates.
76 mins: DaMarcus Beasley's pace wins a free-kick on the left but Vitor Baia is for once untroubled in dealing with the ball into the box.
75 mins: The USA bring on Everton striker Joe-Max Moore for Landon Donovan before Luis Figo takes the corner. Fernando Couto gets his head on it but is penalised for a foul as he does so.
75 mins: Tony Sanneh makes a vital header over his own bar when Portuguese attackers are queuing up beyond him.
73 mins: Portugal make another substitution, bringing on Jorge Andrade for defender Jorge Costa.
71 mins: Portugal's pressure finally pays off as Jeff Agoos scores an own-goal. Pauleta rifles in a dipping cross from the left which Agoos tries to clear right-footed, but he only succeeds in cracking it past Brad Friedel and into his own net.
USA 3-2 Portugal
69 mins: Portugal make their first change, bringing on Paulo Bento for his Sporting Lisbon team-mate Rui Jorge.
69 mins: DaMarcus Beasley is almost punished for giving the ball away to Luis Figo on halfway. Figo floats a perfect pass into the path of Pauleta but the ball sits up and he is unable to keep his shot down.
67 mins: Pauleta is caught offside while chasing Rui Costa's long through-ball played after Fernando Couto had escaped unpunished for a heavy tackle from behind.
66 mins: A mistake by Cobi Jones concedes a corner but Sergio Conceicao's subsequent cross is too long for the Portuguese attackers in the box.
64 mins: Portugal are now beginning to apply sustained pressure and Rui Jorge's cross floats dangerously across the US six-yard box.
62 mins: Pauleta climbs highest to meet a cross but heads back across goal when it looks easier to score. The USA scramble the ball clear but Sergio Conceicao runs it straight back at them, requiring Brad Friedel to save at his feet.
60 mins: Beto wins a free-kick that Luis Figo swings in for the right, only for Fernando Couto to loop his near-post header wide.
58 mins: Beto hits a 25-yard free-kick high and wide after Joao Pinto is fouled.
57 mins: Landon Donovan and DaMarcus Beasley combine well on the left before Beasley's shot flies across the face of goal.
56 mins: The USA immediately strike back, finding more gaping holes in the Portugal defence. Landon Donovan escapes down the left and fires a shot narrowly across goal.
55 mins: Tony Sanneh has to put Fernando Couto's long ball out for a corner under pressure from Pauleta. The kick falls to Jorge Costa who cannot turn the ball into the net from a couple of yards out.
54 mins: Cobi Jones gets in a good position but delays too long and allows Fernando Couto to make a good cover tackle.
53 mins: Jeff Agoos blasts his left-footed free-kick high and wide from the centre of the D.
52 mins: Petit is booked for illegally halting the run of Landon Donovan. Portugal immediately concede another free-kick on the edge of their box when Fernando Couto holds down Brian McBride.
50 mins: Luis Figo turns on the style to jink out of trouble on the left. Sergio Conceicao takes the move on and gives a good return ball to Figo, who is stopped by the US defence.
48 mins: The shouts from the US bench are to move play further up the field to counter the threat Portugal pose when they are allowed to press a deep-lying defence.
47 mins: Fernando Couto complains that the ball is soft but still gets enough power on his long free-kick for it to run through to Brad Friedel in the US goal.
1103 BST: The USA restart in front of an expectant crowd with substitute Cobi Jones on for captain Earnie Stewart.
1047 BST: Referee Byron Moreno blows his whistle to end an action-packed half in which the USA built a three-goal lead before Portugal rallied and at last began to show some of their renowned attacking flair.
Half-time: USA 3-1 Portugal
45 mins (+2): A poor first touch costs Sergio Conceicao a scoring chance inside the USA box.
45 mins (+1): Luis Figo wins a corner on the left which is scrambled away from the far post. The ball drops to Rui Costa 20 yards out and he rifles a shot just wide of Brad Friedel's left-hand post.
44 mins: Pauletta is again close to grabbing a second Portugal goal, this time out-jumping Eddie Pope to head wide of the far post.
42 mins: The action is now end-to-end and Pauletta is inches away from meeting Sergio Conceicao's cross, this time from the left of the field.
39 mins: Beto puts Portugal back in the match with a goal from his team's third corner in succession. The Sporting Lisbon defender heads Luis Figo's dead-ball kick goalwards and then reacts quickest when his effort is blocked by John O'Brien.
USA 3-1 Portugal
36 mins: Portugal are punished yet again for their poor defending. This time, Tony Sanneh rifles in superb cross from the right for Brian McBride to head home the USA's third goal unmarked from close-range.
USA 3-0 Portugal
35 mins: Beto is the first player to be booked, for taking a dive on the right.
34 mins: Jorge Costa is caught waiting for the whistle and it takes a good intervention from Vitor Baia to deny Brian McBride the chance to make it 3-0.
29 mins: The USA extend their lead to 2-0 with an own-goal that sums up the chaos in the Portugal ranks. They make a complete hash of clearing a free-kick to give Landon Donovan the chance to send in a cross that deflects off Jorge Costa and into the net, via Vitor Baia's hand and the near post.
USA 2-0 Portugal
28 mins: Jorge Costa makes a vital tackle on Landon Donovan after Fernando Couto casually gives the ball away in his own half.
25 mins: Portugal at last begin to show signs of finding their passing range. Luis Figo makes space for Rui Costa to swing in a cross from the right, but it flies just beyond the toe of Sergio Conceicao.
23 mins: Luis Figo wins another free-kick but his cross is too deep and easily taken by Brad Friedel.
22 mins: Pauletta gets away from his marker at a Portugal free-kick but glances his header across the face of goal.
21 mins: Landon Donovan again finds space in the Portuguese defence to fire a shot over the bar.
20 mins: The chants ringing out around the stadium are all for the USA. And Portugal are still struggling to find their feet, with Sergio Conceicao wafting an attempted lob way over Brad Friedel's crossbar.
17 mins: Jorge Costa concedes a corner after Landon Donovan gets past Petit on the left and pulls back a low cross. Vitor Baia gets a more positive punch on the ball when the corner comes in.
16 mins: The USA are playing some neat football and when they counter-attack from a loose pass by Beto, Vitor Baia is again required to sweep up.
14 mins: Play immediately switches to the other end and Vitor Baia has to be quick off his line to beat DaMarcus Beasley to a route one pass.
13 mins: Portugal are begining to threaten in an open game and Pauletta heads wide from Sergio Conceicao's right-wing cross.
13 mins: Jeff Agoos covers Pauleta's through-ball down the inside-right channel.
11 mins: Luis Figo curls in a right-wing free-kick which Joao Pinto can only head down under pressure from John O'Brien, allowing Brad Friedel to collect.
9 mins: Portugal get their first chance when Eddie Pope concedes a free-kick for handball 25 yards from goal. However, Sergio Conceicao can only drive his shot into the US wall.
7 mins: The USA are inches from taking a two-goal lead. Vitor Baia elects to punch Earnie Stewart's free-kick but the ball rebounds straight back past him off Landon Donovan and dribbles agonisingly wide.
6 mins: Petit chops down Landon Donovan on the edge of the Portuguese penalty area.
3 mins: Earnie Stewart's long shot is deflected wide for a corner. Vitor Baia parries the initial header from Brian McBride when the dead-ball comes in, but John O'Brien hammers the rebound home from close range.
USA 1-0 Portugal
1 min: Portugal threaten from the start, with Jeff Agoos having to head clear a cross straight away.
1000 BST: Portugal kick off in front of a colourful Suwon crowd including many flag-waving supporters of both teams and at least one Elvis impersonator.
But the biggest pre-match cheer is for the sight of South Korea coach Guus Hiddink on the stadium's big screens.
Portugal receive a big boost as Luis Figo is passed fit to start the game.
The Real Madrid midfielder declared himself fully recovered from an ankle injury that has troubled him since February.
Figo's presence is bad news for the USA, and is compounded by the absence of their captain Claudio Reyna and striker Clint Mathis.
Both men are ruled out by injury.
In the other main area of contention, Blackburn goalkeeper Brad Friedel gets the nod ahead of his Tottenham rival Kasey Keller.
USA: Brad Friedel, Frankie Hejduk, Pablo Mastroeni, John O'Brien, Earnie Stewart (capt), Jeff Agoos, DaMarcus Beasley, Brian
McBride, Landon Donovan, Tony Sannah, Eddie Pope.
Portugal: Vitor Baia, Jorge Costa, Fernando Couto (capt), Luis Figo, Joao Pinto, Pauleta, Rui Costa, Sergio Conceicao, Petit, Beto, Rui Jorge.
Referee: Byron Moreno (Ecu)