Summary
Barcelona go four points clear at top
Suarez controls long ball and slots home winner
Messi 43 goals this season; Ronaldo 42
Messi 21 El Clasico goals; Ronaldo 15
Live Reporting
Tom Rostance
Messi the master?published at 18:48 Greenwich Mean Time 22 March 2015
Simply the best?published at 18:47 Greenwich Mean Time 22 March 2015
18:47 GMT 22 March 2015Brazil legend Pele says Lionel Messi has outshone Cristiano Ronaldo as "the best in the world" over the past decade.
Argentina and Barcelona star Messi, 27, edges Real Madrid and Portugal's Ronaldo, 30, 4-3 in Ballon d'Or wins.
"At the moment people always try to compare Ronaldo with Messi [but] it's a different style," the three-time World Cup winner told the BBC's Sportsweek in between flogging sandwiches.
The 74-year-old added: "They are two great players, but in the past 10 years the best in the world was Messi.
"Bobby Charlton, Bobby Moore, George Best - they were the same level as Messi. We had in Brazil Zico, Rivaldo."
An age-old debate that will rumble on and on...
'Isco is the new golden boy'published at 18:45 Greenwich Mean Time 22 March 2015
18:45 GMT 22 March 2015Spanish football writer Andy West
"Sergio Ramos is back. Luka Modric is back.
"When you also consider Gareth Bale's return to goalscoring form last weekend and the consistent excellence of Isco, Spanish football's new golden boy, there are plenty of reasons to believe that Real can quickly return to the brilliance which saw them set a new Spanish record of 22 consecutive victories earlier this season.
"If they can do it on Sunday and claim all three points at the Nou Camp, we might even see Cristiano Ronaldo smiling again."
Postpublished at 18:45 Greenwich Mean Time 22 March 2015
18:45 GMT 22 March 2015Our man in the Nou Camp Andy West is taking his place in the stands. The turnstiles have just opened in the cavernous stadium, the floodgates may well follow soon enough.
Goals tonight? Let's hope so...
'The crisis is with Real'published at 18:41 Greenwich Mean Time 22 March 2015
18:41 GMT 22 March 2015Bolton's former Barcelona forward Eidur Gudjohnsen told BBC Sport: "You can compare it to an FA Cup final. Three or four weeks before El Clasico the hype starts and it builds up to a huge occasion. It is not just bragging rights, it is more than that.
"In one of the games I played someone wrote on a board in the dressing room; 'Don't worry boys there's only 400 million people watching.'
"I'm just glad to have known the feeling of playing in a game like that.
"I always fancy Barcelona. The three forwards they have have finally gelled and found a good balance with Luis Suarez in good form.
"Real Madrid are having the opposite run of form, they don't look balanced and are conceding a lot of goals. There seems to be unrest and the crisis at the moment is on Real's side."
Join the debate at #bbceurofootypublished at 18:40 Greenwich Mean Time 22 March 2015
18:40 GMT 22 March 2015Kindinu Kakumba: Real know that a victory will send them top of La Liga and they will be aiming for that.
Stat attackpublished at 18:39 Greenwich Mean Time 22 March 2015
18:39 GMT 22 March 2015There has not been a goalless draw in 36 meetings between Barcelona and Real Madrid. The last 0-0 came at the Nou Camp in November 2002 and if we have one tonight I'll eat my hat. Pass the sauce.
Between them, Real Madrid and Barcelona have won 54 Spanish league titles, 45 Copa del Reys and 14 European Cups.
Real Madrid have scored the most goals from outside the box this season - eight - while Luis Enrique's Barca side are the only team in La Liga still to concede a goal from outside the box.
Shooootttt!
The title decider?published at 18:36 Greenwich Mean Time 22 March 2015
18:36 GMT 22 March 2015First v second, a point between the two sides - but Barca boss Luis Enrique insists that tonight's crunch tie will not settle the La Liga title.
It's an important game but not a decisive one," said Enrique, who played for both sides.
"These games are certainly different to any others. They are our eternal rivals. There's also our head-to-head goal difference to bear in mind.
"There are no clear favourites in games like these. But playing in front of our own fans always gives us that extra boost. This is a nice chance to put some space between us.
"It's not quite as intense as a manager. You have to control what's happening on the pitch. It's more about keeping your cool and making decisions at the right time."
Real Madrid have won the last two Clasicos, and could make it three in a row for the first time since 1978.
However, Barcelona have not lost at home to their rivals while leading the league since 1929-30.
Postpublished at 18:31 Greenwich Mean Time 22 March 2015
18:31 GMT 22 March 2015From New York to Tokyo; Lagos to Santiago, the world's eyes will be turned on the Nou Camp this evening.
Or morning, if you are following from the east.
On a domestic basis, this is all about winning La Liga and settling scores. On a global scale it's about the best players in the world on the one pitch.
Are you set?
'Legends in the building'published at 18:27 Greenwich Mean Time 22 March 2015
18:27 GMT 22 March 2015It reads like a footballing who's who.
Lionel Messi. Cristiano Ronaldo. Thierry Henry. Michael Owen.
Neymar. Ruud van Nistelrooy. Roberto Carlos. Davor Suker.
Andres Iniesta. Alexis Sanchez. Xavi. Samuel Eto'o.
David Villa. Raul. Johan Cruyff. Gary Lineker.
Arjen Robben. Ronaldinho. Zlatan Ibrahimovic. Patrick Kluivert.
Zinedine Zidane. Ronaldo. Alfredo di Stefano. Luis Figo.
Fernando Morientes. Nicolas Anelka. Rivaldo. Ronald Koeman.
Ivan Zamorano. Michael Laudrup. Ferenc Puskas. Luis Enrique.
You have to be some player to play in El Clasico, never mind score in one. The list of legends to emboss their name on the Clasico history books is almost endless, with every man above scoring in at least one league clash between Barcelona and Real Madrid.
If you follow one European game all season, it's this one. Who will stamp their name in the record books tonight?