Fernando Hierro takes charge of Spain for the first time
Real Madrid star Cristiano Ronaldo looks to shine for Portugal
Iran beat Morocco 1-0 in the earlier Group B opener
Today's matches: Group C - France v Australia (11:00 BST, BBC TV, 5 live), Peru v Denmark (17:00 BST, BBC TV, 5 live)
Group D - Argentina v Iceland (14:00 BST, ITV, 5 live), Croatia v Nigeria (20:00 BST, ITV, 5 live)
Portugal 2-1 Spain
Danny Murphy
Former England midfielder on BBC One
David de Gea is one of the best in the world and you wouldn't think he would have any problem with that. He has had nothing to do for the last half an hour and maybe that's why, but this should never go in.
Portugal 2-1 Spain
Chris Waddle
Ex-England winger on BBC Radio 5 live
You couldn't say De Gea would do something like that, he's that good. You can't believe what you are seeing. You feel for him, very rarely makes a mistake he's a top class keeper.
Image source, Reuters
Cristiano Ronaldo
It's a shocker. An absolute howler. David de Gea has had a Loris Karius moment and Portugal have the lead again.
Of course, it's Cristiano Ronaldo who benefits. From the edge of the box, he shoots low and left-footed. De Gea should have it covered, he gives it the long barrier like a cricket fielder.
Somehow, it slips through his hands, off his right foot and into the net. From nowhere, Portugal lead.
'It's gone through him' - De Gea mistakes gifts Ronaldo his second goal
Portugal 1-1 Spain
I thought I heard that Ronaldo's legs were going? Every time he gets the ball he's got the speed of Usian Bolt. Invariably it's during a Portugal break, with Spanish defenders reversing...
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Adam: Not enough is said about the quality of Iniesta, maybe it's because he goes about his business quietly, but the guy is consistently awesome.
Bishnu: My oh my. Iniesta and a football, just like a man and his best friend, just like a master craftsman and his tools, an opera singer and his/her notes.....I can go on and on and on...
Portugal 1-1 Spain
Fernando Hierro, black hair slicked back, has only a white shirt between him and the night sky. It might be that the jeers are when a team isn't attacking. When the ball is kept by defenders, the crowd urges them on. It's like the Roman Colosseum.
Image source, ReutersPortugal 1-1 Spain
For the first time in living memory, Portugal have the ball. They are intent on keeping it too. Jeers from the stands...
Portugal 1-1 Spain
Cristiano Ronaldo shows that he doesn't mind getting his hands dirty, appearing in his own box to defend the corner. Swung in from the left, Pepe trying to clear, behind the Portugal goal from Sergio Busquets.
Image source, AFP#bbcworldcup
Tom Miszkowski: Spain going through the gears now but Portugal looking dangerous on the break, game set up quite nicely
Theo HV: Ah so this is what football looks like... the tournament has finally kicked off!
Rob Cogle: Going to be a red in this game, Costa vs Pepe is enough for at least one
Portugal 1-1 Spain
Just joining? Where on earth have you been? You've missed a brilliant equaliser from Diego Costa and an attempt from Isco that nearly broke the crossbar. Spain corner coming up...
'His critics well and truly answered' - Costa pulls Spain level
'Spain think that's in' - Isco strikes underside of bar
Portugal 1-1 Spain
Chris Waddle
Ex-England winger on BBC Radio 5 live
Spain, sometimes they frustate when the appear to just be passing slowly, but when they go through the gears so quickly, teams can't live with it. Great move.
Image source, Getty ImagesPortugal 1-1 Spain
Danny Murphy
Former England midfielder on BBC One
We are talking about wonderful football from super talented players. I think Isco has been brilliant and Spain are really starting to cause Portugal problems with their movement off the ball. They are all on the same wavelength.
Portugal 1-1 Spain
Patrick Jennings
BBC Sport in Russia
Iniiiieeeesta. From every corner of the ground. Spain are beginning to look like Spain again.
Image source, ReutersPortugal 1-1 Spain
Inches away. Andres Iniesta gets half a yard in the Portugal box, swinging a left peg at Isco's pass. It's a bit of a scuff, but still beats Rui Patricio. It's past the far post, though.
Portugal 1-1 Spain
Just for a change, Spain come down the right. Nacho tries to find a way, but is crowded out. When Portugal do get the ball, Diego Costa is the man chasing back to halfway, winning it back.
Portugal 1-1 Spain
Image source, .A breathless first half an hour, but who do you think have been the best players so far?
Portugal 1-1 Spain
Danny Murphy
Former England midfielder on BBC One
This has been the best 30 minutes of football at the tournament so far. The tempo has been great. Portugal can take positives from this game and they have opened Spain up on occasion, especially from those counter attacks. Plenty left in this game for them.
Portugal 1-1 Spain
The atmosphere is heavy, expectant. This is the first match played under the cover of darkness and you can't help but feel like that has cranked things up a notch. Spectators are getting a pain in the neck for turning towards the Portugal half. David de Gea is having half a lager.
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Russell Shanks: The quality Costa posesses when he's on focus is about the same as the level of stupidity Pepe shows falling like a sack of spuds.
Dan: Love the way the players have a mini game of charades every time they want to go to VAR!
Donald: Such a determined performance from Diego Costa. Superb finish, now we know why Alvaro Morata did not make it to Russia
Image source, ReutersPortugal 1-1 Spain
We've only had half an hour. There's been more incident than the other three games put together. It may (I stress 'may') have settled down a little. Portugal are chasing shadows. Spain are passing the parcel.