It was noisy ahead of the meeting between Wales and Iran on site in Qatar.
The Iranian players - who, before the opening match against England, refrained from singing the national anthem - suddenly sang along.
The players then took to the pitch and pressured Wales in the battle for second place behind England in Group B.
Wales, who came from 1-1 against the USA in the opener, were badly out several times but looked like they could escape with a point.
But then in the eighth extra minute, substitute Rouzbeh Cheshmi fired a shot that made it 1-0.
Double pole hits
Already in the 16th minute, Ali Gholizadeh was able to push the ball into the open goal.
After var review, the case was dismissed.
In the second half, Wales - and above all goalkeeper Wayne Hennessey - had to breathe a sigh of relief again.
In the space of a minute, Iran hit the post twice.
First, Bayer Leverkusen star Sardar Azmoun broke free and nicked Hennessey's left post.
Then Ali Gholizadeh got the ball and screwed the ball into the far post.
And it would be Wayne Hennessey who came into focus during the final minutes.
With six minutes remaining, the Wales keeper came out the wrong way and collided with Iranian forward Mehdi Taremi.
Referee Mario Alberto Escobar Toca first showed a yellow card - but after review, Henessey was sent off.
Wales held out with a man down until the eighth minute of injury time - but then everything came crashing down.
First Cheshmi thundered in 1-0 and a minute later Iran also made it 2-0 through Ramin Rezaeian.
Iran, making their sixth World Cup, have never made it past the group stage.