It is little surprise Real Madrid are reportedly interested in Manchester City full-back Joao Cancelo.

The Portuguese star is the only player to have started all 15 of City’s Premier League and Champions League games this term.

Ahead of City’s trip to Borussia Dortmund tonight, we look at Cancelo’s unique role and why Pep Guardiola cannot afford to sell him.

No rest for the wicked

Guardiola loves to rotate his side to deal with the incredibly busy fixture list, yet Cancelo is rarely named among the subs.

A combination of injuries, suspensions and the fact the 28-year-old performs such a unique role means he is almost impossible to replace.

After a slow start following his move from Juventus in 2019, Cancelo has been a key figure for Guardiola, who admitted in February that it has not always been an easy relationship.

Guardiola said: "We struggled when he arrived, we did not agree on many things, partly because of my mistakes, but now I’m delighted he’s fully happy and can play here for the next seasons.

"He can play in many positions, can play every day, physicality, he’s so funny and loved in the locker room."

Unique position

What is different about Cancelo is how influential he is going forward and how much he is allowed to drift inside.

The event map above shows he spends much more time nearer the opposition’s corner flag than his own, as well as being heavily involved just outside their area.

It is why his two goals this term are the best for a full-back in the top flight. Only Trent Alexander-Arnold and Southampton’s Romain Perraud have had more shots and nobody has come close to his 36 attempted and 22 completed take-ons.

He ranks top for passes attempted, passes completed, final third passes completed, touches and possessions won in the attacking third among all full-backs.

Alongside the likes of Phil Foden, Kevin de Bruyne and Erling Haaland, Cancelo is an attacking weapon.

Defensive lapse

For all his attacking influence, Cancelo’s defensive ability was put under the microscope last week when he was at fault for Liverpool’s winner against City.

Mohamed Salah outmanoeuvred the full-back to get on the end of Alisson’s ball over the top in a costly error.

Ex-England defender Rio Ferdinand said: "Cancelo is great with the ball but defensively one-vs-one, that’s not his best attribute — there’s still improvements to be made.

"But he doesn't get left isolated a lot like that so he’s fine. What he does with the ball far outweighs what he does defensively."

While it may not be his strength, Cancelo does not ignore his duties in a side with a mean defensive record.

Among full-backs, he has the fifth most interceptions, fourth most tackles and the 22 aerial duels he has won are the third most.

Burnout

City’s main concern currently is not whether the 28-year-old  — contracted until 2027 — will stay, but when to give him a rest.

Cancelo will be a key part of Portugal’s side in Qatar for the World Cup, meaning he will play an astonishing number of games this season.

Though they have already qualified for the knockout stages of the Champions League, Guardiola will want to win tonight and ensure top spot.

Added to that, Sergio Gomez is suspended and Kyle Walker is injured, meaning resting Cancelo seems a long shot.

But the Spaniard will know he cannot keep naming him in the starting XI — missing him for one game would be preferable to a fatigue-related injury ruling him out for weeks or months.