USA and Portugal played to an incredible 2-2 draw in Manaus on Sunday evening, with Silvestre Varela bagging a 95th-minute header to force a share of the spoils.
Nani had given the Seleccao the lead in the opening exchanges, which they held for the first half, but Jermaine Jones hit a screamer from distance to level it in the second period.
Clint Dempsey then chested the USA ahead. The win for the Americans looked sealed, but Varela headed home at the death after a sublime Cristiano Ronaldo cross.
Starting XIs and Formations
USA opted for a deep-set 4-2-3-1 formation with Clint Dempsey up front, Michael Bradley as the most advanced midfielder and Matt Besler back in at centre-back.
Portugal played their usual 4-3-3 but with Helder Postiga up front and Andre Almeida out of position at left-back. Cristiano Ronaldo drifted around as he pleased.
Paulo Bento made a few tweaks to his 4-3-3 for this game, making it far more free-flowing and flexible when in possession.
Ronaldo first popped up on the right, double-teaming DaMarcus Beasley with Nani, then moved to the centre to try his luck in the middle. He eventually ended up on the left but kept moving, and centre-forward Postiga would simply readjust to balance out the formation.
This stopped when Postiga went off injured and was replaced by the more conventional target man in Eder, and Portugal became far more predictable on the attack.
Portugal fielded Almeida high up on the left as a left-back-cum-left midfielder, and while that gave them great width in attack, it allowed USA right-back Fabian Johnson to steam forward regularly unchallenged.
His runs pulled Raul Meireles out of position to cover at left-back and reorganised the Seleccao's midfield. Johnson was very economical in his choices and with the ball when in behind, and the U.S. soon realised that he was the key outlet to hit when moving forward.
Graham Zusi and Dempsey began drifting to the right to combine, and several chances were created as a result.
Portugal defended in a high-block, pushing five players up above the halfway line and clouding out the space in front of the U.S. defence.
The high stance gave Jurgen Klinsmann's deep-lying ball-players very few options to pass to, and it resulted, largely, in long balls down the channel for Dempsey to use.
He latched onto several and fashioned chances inside the box, but Michael Bradley and Kyle Beckerman struggled to get onto the ball in the final third throughout.
With Almeida part of the high-block, it opened space for Johnson; so if Dempsey wasn't making runs, they'd play it to his feet and let him go.
U.S. hearts broke as Ronaldo's late cross met the head of Varela in the 95th minute, but things still look very, very promising for Klinsmann's men.
They need a draw against Germany to assure qualification, and even if they lose, Portugal need one hell of a goal swing.
The match became very stretched late on. It was a bit of a free-for-all, where both sides proved they can attack with pace and power. Klinsmann in particular was delighted with his side, telling reporters live on TV after the game:
"[It was] an amazing performance by us; there's nothing more you can ask for. Now we have to go and beat Germany. We [carry] confidence into the next game."