As the age old saying goes, there are three certainties in life: death, taxes and Luka Modric bossing it in midfield for Real Madrid.

The Croatian was in action against Manchester United in the UEFA Super Cup on Tuesday and once again ran the show alongside his partner in crime, Toni Kroos.

Modric and Kroos are widely regarded as the best midfield duo on the planet due to their combination of energy, creativity and skill.

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Defensively they're not the strongest, of course, and that's why they have Casemiro alongside them to break up play and protect the back four.

Against United, the trio dominated in midfield, with Casemiro breaking the deadlock in the 24th minute with a fine finish from Dani Carvajal's cross.

It's incredible to think that Modric was voted the worst signing of the year following his debut season in La Liga.

The 31-year-old signed from Tottenham for £30 million in 2011 and since that underwhelming first campaign, he's developed into arguably the world's best midfielder.

Indeed, back in April, Zinedine Zidane labelled Modric as one of his most important players because of the Croatian's "tranquility".

He said, per Sky Sports: "It's his tranquillity. It's his tranquillity with the ball. I have the best players and we could talk about any of them.

"But if you ask me about Luka, I have to talk about his calmness with the ball at his feet. La tranquilidad. That's what he gives to the team when he's playing well. He makes the rest play."

Modric will play a pivotal role in defending Real's La Liga and Champions League titles this season, but he won't be available for the Spanish Super Cup first leg against Barcelona on Sunday.

And why? Well, quite incredibly, it's because of a ban Modric was handed three years ago in the second leg of the 2014 Spanish Super Cup against Atletico Madrid.

Modric received two yellow cards that day and he's now being punished for it, Marca reports.

It's certainly harsh and it wouldn't be overly surprising if Modric had completely forgotten about the ban, considering it happened a whole three years ago.

But nevertheless, he will be unavailable to Zidane, who must now identify who to play alongside Kroos and Casemiro against Barcelona. Isco is one option, while Mateo Kovacic is another.