Exhausted, he glanced towards the sidelines, but Max Allegri had already recognised his midfielder needed to be replaced. Mario Lemina was ready to enter the fray in his place and the fourth official lifted the electronic board above his head to signal the substitution. When the display showed it was the man in the No.8 shirt who was to make way, Juventus Stadium rose as one to acknowledge his efforts in the 73 minutes that had been played.

“Claudio Marchisio alè shalalallllaa” they sang, applauding the Italian international as he jogged off the field with the Bianconeri comfortably leading Sampdoria last October.

Despite his tired limbs, the then-30-year-old returned their affection as he always has, because supporters who follow the reigning Serie A champions are his people and he is their true representative on the pitch.

Born in Turin, he signed for the club in 1993 and, aside from spending a year with Empoli to gain experience, he has remained there ever since. He has always been a fan of the club, but over the past few years his importance to the team and its fans has grown exponentially.

Marchisio has never courted attention the way many of his team-mates have, there is no self-serving publicity machine behind him nor any extravagant claims from an agent looking to maximise his value.

Now, though, he is a Chelsea transfer target. His former coach in Turin, Antonio Conte, is keen to be reunited with the 31-year-old who would act as his on-field lieutenant at Stamford Bridge.

When Andrea Pirlo, Arturo Vidal and Paul Pogba were part of the squad, he was often the odd man out, the one few people discussed and even fewer were interested in signing.

Yet as that trio departed one by one for lucrative deals in New York, Munich and Manchester respectively, Marchisio remained with the Old Lady and continued to deliver when it mattered most.

As such, seeing him collapse in agony during a routine win over Palermo in April caused much anguish. Clutching his left knee, it was later revealed Marchisio had torn his anterior cruciate ligament, surgery ruling him out of Euro 2016 and leaving him facing a long road back to fitness.

With the same effort and dedication that typifies his play, Il Principino – “the little Prince” – began working towards his comeback, six months of intensive rehabilitation culminating in that emotional comeback against Sampdoria in October.

.@ClaMarchisio8 vs Sampdoria (26/10/16) via @StatsZone. Six months out with torn ACL, returns with this all-action display. Incredible. pic.twitter.com/i0UX2rBg6b — Adam Digby (@Adz77) January 6, 2017

The FourFourTwo Stats Zone graphic in the tweet above shows just how complete a performance it was from Marchisio, who recorded one tackle, two interceptions, nine ball recoveries and one clearance.

He also connected with 39 of his 44 pass attempts (88.6%), completed his one take-on and won the only headed duel that he contested, a statistical return that not only encapsulates his all-round brilliance but also his sheer determination.

Such a display would be admirable at the best of times, but to do so six months after destroying your knee in the same arena cannot he praised highly enough. It is far from a one-off this season either.

Marchisio is arguably Juve’s most important and most influential player despite the continued brilliance of Paulo Dybala plus the high-profile arrivals of Gonzalo Higuaín and Miralem Pjanić.

Indeed, without Marchisio, Juventus look toothless and disorganised. He is the straw that stirs the drink, the glue that holds the team together and the positive force that underpins everything the Bianconeri are trying to accomplish.

Diligent in possession, Marchisio has completely reinvented himself as a player since Allegri replaced Conte on the Juve bench. Under the Chelsea boss, he was a box-to-box midfielder, his energy used to protect a full-back and Pirlo before bursting forward to join the attack.

Now, with the Bianconeri robbed of the aforementioned bearded genius, it is Marchisio who occupies the central role, dictating the play and shielding the defence. Unlike his predecessor however, he is not a static metronome, instead popping up all over the pitch to make crucial passes.

But it is not just on the ball where Marchisio excels, as his tactical awareness and ability to read the game see him winning tackles and making interceptions with incredible regularity. Again he does not simply stand around waiting for his opportunity, often pressing into an area where he senses the opposition will attack before using his superb timing to intervene.

Finally, he has become a true leader, helping the club’s new arrivals find their way and learn what is expected of them once they pull on the famous black and white stripes.

“The old guard and the Italian nucleus is important for us, because we’re able to convey what it means to be at Juventus and to wear this shirt,” Marchisio told Sky Italia in November. “I’m teaching this to the youngsters just as it was taught to me.”

He went on to say: “You don’t need the armband to be a captain,” but admitted that whenever he does lead the side “I’m definitely emotional.” But even then there is no dramatic outburst or chest-thumping, merely a man leading by example and doing his job.

He is perhaps not be the best midfielder in the world, but he is still the one of game’s most overlooked and underrated. Except at Juventus Stadium, where his name is sung the loudest and cheered the longest.

It is for all those reasons Chelsea would be lucky to get him – and Juventus foolish to sell him.