Already the free-kick count is nudging double figures. The tackles are flying and this is already tasty. The referee is set for a busy night.

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First shot in anger comes from Bayern - Thomas Muller blazes a great chance over the bar after Swiss keeper Roman Bürki's unconvincing clearance.

Jurgen Klopp and his heavy metal football may have left for Anfield but there's an astonishing wall of noise inside the ground. Tentative start by both sides. Loud jeers each time a Bayern shirt touches the ball. Hostile.

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Dortmund get Der Klassiker under way. 

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There's an intimidating cascade of sound inside Signal Iduna Park. There's more than 80,000 packed inside - most wearing yellow. There's a splattering of red with Bayern bringing a decent number of fans. We're almost ready to go.

Borussia Dortmund XI: Burki, Piszczek, Bender, Hummels, Schmelzer, Gundogan, Weigl, Durm, Mkhitaryan,Aubameyang, Reus.

Bayern Munich XI: Neuer, Lahm, Kimmich, Alaba, Bernat, Alonso, Vidal, Robben, Muller, Costa, Lewandowski.

This game is so huge that even Germany boss Joachim Low has had his say.

"The Bundesliga could be really exciting after this weekend if Dortmund beat Bayern," says Low.

They are coming up to the hour mark in Paris where it remains goalless. PSG need two more wins to make sure of a fourth straight Ligue 1 title.

Image source, getty

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Borussia Dortmund boss Thomas Tuchel: "We have a situation now where we can get very close to them. We've worked hard for this situation. To a certain degree, losing 5-1 in Munich has made us into a team we are now."

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Dortmund have a score to settle. Back in October they lost at Bayern - heavily. Former Dortmund striker Robert Lewandowski scored twice in a 5-1 thrashing. 

Bayern have won the last three Der Klassiker's with Dortmund's last win a 3-0 success at Bayern in April 2014.

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Bayern Munich boss Pep Guardiola: "No matter what happens, the league title is not going to be decided until the final game of the season. The title won't be done and dusted if we win."

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Just when it seemed the race for the Bundesliga title was turning into a predictable one-horse contest, Bayern Munich went and did the unthinkable by losing at home for the first time all season.

Will Wednesday's 2-1 defeat to Mainz turn into a season changer? 

Having held an 11 point advantage at the top as recently as 22 January, Bayern's lead will be cut to just two points if second-placed Borussia Dortmund make it five straight league wins.

Little wonder this fixture is about to bring Germany to a standstill.

Half an hour to kick-off in Der Klassiker.

What does this result mean to the title race?

Not a lot, really. Real remain third although they are now just one point behind second-placed Atletico Madrid having played one more game.

Leaders Barcelona are eight points clear.

Brilliant display of firepower from Real in the second half. 

Cristiano Ronaldo will get the headlines for his four goals but the good news for Wales fans is that Gareth Bale is back.

Two additional minutes.

Gareth Bale is playing like a man determined to make up for lost time. The game has long since been won but the Wales forward is teasing and tormenting the Celta defence in the closing moments.