They walk among us. They talk like us. They may even look like us. But deep down, underneath their breathable apparel and questionable tattoos, professional athletes are not really the same as you and me. And day two of the Melbourne Test was one of those days that proved it.

Alastair Cook is definitely not like you and me. He is one of those cricketers who has been part of the England furniture for so long that you occasionally fall into the trap of thinking you know him. In fact, the cleavage between what we think we know about Cook and what we actually do is probably as wide as it has been with any celebrated England player.

The common assumption on this tour has been that it may be his last. Not just his last Ashes tour; his last, full stop. The runs have dried up. The body language has been curiously inert. Captain Joe Root seems to talk tactics far more with Stuart Broad and James Anderson than with him. We all think we know how this tale ends.

Ashes fourth Test in pictures Show all 40 1 /40 Ashes fourth Test in pictures Ashes fourth Test in pictures mcg.jpg Over 88,000 people attended the first day's play at the Melbourne Cricket Ground. Getty Ashes fourth Test in pictures tom-curran.jpg Tom Curran reacts to his near-miss after dismissing David Warner on a no ball. Getty Ashes fourth Test in pictures chris-woakes.jpg Chris Woakes celebrates taking the wicket of Cameron Bancroft. Getty Ashes fourth Test in pictures david-warner1.jpg David Warner celebrates reaching his century. Getty Ashes fourth Test in pictures ashes-1.jpg David Warner celebrates scoring a century against England. Getty Ashes fourth Test in pictures david-warner.jpg Warner salutes the crowd as he leaves the field having made 103. Getty Ashes fourth Test in pictures usman-khawaja.jpg Stuart Broad celebrates after dismissing Usman Khawaja. Getty Ashes fourth Test in pictures steve-smith.jpg Steve Smith took little time to race to his half-century. Getty Ashes fourth Test in pictures stuart-broad1.jpg Stuart Broad appeals for the wicket of Shaun Marsh on his very first ball. Getty Ashes fourth Test in pictures stuart-broad.jpg Marsh was saved on review by an umpire's call. Getty Ashes fourth Test in pictures pictures-of-the-day-3.jpg TOPSHOT - Australia's Steve Smith drops a catch from England batsman Alastair Cook on the second day of the fourth Ashes cricket Test match at the MCG in Melbourne on December 27, 2017. / AFP PHOTO / WILLIAM WEST / --IMAGE RESTRICTED TO EDITORIAL USE - STRICTLY NO COMMERCIAL USE--WILLIAM WEST/AFP/Getty Images AFP/Getty Ashes fourth Test in pictures stuart-broad.jpg Stuart Broad successfully appeals for lbw against Jackson Bird. Getty Ashes fourth Test in pictures alastair-cook.jpg Alastair Cook registered his highest score of the Ashes tour at the MCG. Getty Ashes fourth Test in pictures alastair-cook-3.jpg Alaistair Cook celebrates reaching his century on the second day of the fourth Test against Australia. Getty Ashes fourth Test in pictures josh-hazlewood.jpg Josh Hazlewood celebrates dismissing Joe Root for 61. Getty Ashes fourth Test in pictures joe-root.jpg Joe Root hooks Josh Hazlewood to Nathan Lyon. Getty Ashes fourth Test in pictures dawid-malan.jpg Dawid Malan made just 14 before being trapped LBW by Josh Hazlewood. Getty Ashes fourth Test in pictures jonny-bairstow.jpg Jonny Bairstow is caught behind by Tim Paine off Nathan Lyon. Getty Ashes fourth Test in pictures moeen-ali.jpg Moeen Ali edges Nathan Lyon to Shaun Marsh for 20. Getty Ashes fourth Test in pictures pat-cummins.jpg Pat Cummins celebrates dismissing Chris Woakes for 26. Getty Ashes fourth Test in pictures tom-curran1.jpg Tom Curran is struck by the first ball he faces before getting out four just 4. Getty Ashes fourth Test in pictures stuart-broad2.jpg Stuart Broad provided strong support for Alastair Cook to help him reach his double century. Getty Ashes fourth Test in pictures stuart-broad3.jpg Stuart Broad celebrates reaching his half-century. Getty Ashes fourth Test in pictures steve-smith1.jpg Steve Smith dropped Alastair Cook twice during the first innings. Getty Ashes fourth Test in pictures alastair-cook.jpg Alastair Cook celebrates reaching his double century on day three of the fourth Test Getty Ashes fourth Test in pictures alastair-cook1.jpg The Barmy Army applaud Alastair Cook's double-century at the MCG. Getty Ashes fourth Test in pictures james-anderson2.jpg Pat Cummins dismissed James Anderson with the first ball of the day to end England's innings. Getty Ashes fourth Test in pictures alastair-cook2.jpg Alastair Cook was left stranded on 244 after batting for the entire England innings. Getty Ashes fourth Test in pictures cameron-bancroft.jpg Cameron Bancroft is dismissed by Chris Woakes. Getty Ashes fourth Test in pictures usman-khawaja1.jpg James Anderson celebrates dismissing Usman Khawaja. Getty Ashes fourth Test in pictures james-anderson-joe-root.jpg James Anderson and Joe Root spent the most time looking after the ball Getty Ashes fourth Test in pictures james-anderson1.jpg Australian media accused James Anderson of ball tampering during the fourth day of the fourth Test Getty Ashes fourth Test in pictures james-anderson.jpg James Anderson will not face any action over the allegations Getty Ashes fourth Test in pictures england-australia.jpg MELBOURNE, AUSTRALIA - DECEMBER 30: Joe Root, captain of England celebrates after dismissing David Warner of Australia during day one of the Fourth Test Match in the 2017/18 Ashes series between Australia and England at Melbourne Cricket Ground on December 30, 2017 in Melbourne, Australia. (Photo by Scott Barbour/Getty Images) Getty Images Ashes fourth Test in pictures england-australia-2.jpg MELBOURNE, AUSTRALIA - DECEMBER 30: Jonny Bairstow of England celebrates after dismissing Shaun Marsh of Australia with Joe Root and his teammates during day one of the Fourth Test Match in the 2017/18 Ashes series between Australia and England at Melbourne Cricket Ground on December 30, 2017 in Melbourne, Australia. (Photo by Scott Barbour/Getty Images) Getty Images Ashes fourth Test in pictures england-australia-3.jpg MELBOURNE, AUSTRALIA - DECEMBER 30: Steve Smith of Australia hits the ball to make his century during day one of the Fourth Test Match in the 2017/18 Ashes series between Australia and England at Melbourne Cricket Ground on December 30, 2017 in Melbourne, Australia. (Photo by Michael Dodge/Getty Images) Getty Images Ashes fourth Test in pictures england-australia-4.jpg Australia's captain Steve Smith celebrates scoring his century against England on the final day of the fourth Ashes cricket Test match at the MCG in Melbourne on December 30, 2017. / AFP PHOTO / William WEST / -- IMAGE RESTRICTED TO EDITORIAL USE - STRICTLY NO COMMERCIAL USE -- (Photo credit should read WILLIAM WEST/AFP/Getty Images) AFP/Getty Images Ashes fourth Test in pictures england-australia-5.jpg MELBOURNE, AUSTRALIA - DECEMBER 30: Steve Smith of Australia (L) and Joe Root of England shake hands after the drawn result during day one of the Fourth Test Match in the 2017/18 Ashes series between Australia and England at Melbourne Cricket Ground on December 30, 2017 in Melbourne, Australia. (Photo by Michael Dodge/Getty Images) Getty Images Ashes fourth Test in pictures england-australia-6.jpg MELBOURNE, AUSTRALIA - DECEMBER 30: England players thank the Barmy Army for their support after the dran result during day one of the Fourth Test Match in the 2017/18 Ashes series between Australia and England at Melbourne Cricket Ground on December 30, 2017 in Melbourne, Australia. (Photo by Michael Dodge/Getty Images) Getty Images Ashes fourth Test in pictures england-australia-7.jpg MELBOURNE, AUSTRALIA - DECEMBER 30: Steve Smith of Australia (R) and Joe Root of England shake hands after the drawn result during day one of the Fourth Test Match in the 2017/18 Ashes series between Australia and England at Melbourne Cricket Ground on December 30, 2017 in Melbourne, Australia. (Photo by Michael Dodge/Getty Images) Getty Images

And yet, remember: you may think you know Cook, but unless you are his wife, a member of his family or one of his very tight circle of friends, you probably don’t. What really spins the cogs under that tousled jet-black mane of his? What drives him? Records? Money? Love of the game? Love of the battle? Love of the team?

Is he one of those openers - Dean Elgar comes to mind - who needs the thrill of the Test match arena to stir him, who relishes the combat, the test of nerve? Or is he in the Marcus Trescothick vein, an opener who simply adores batting, to the extent where you could see him opening the batting for Somerset over-60s with grey hair, rosy cheeks and a bit of a paunch? Or is he a Geoff Boycott - give everything for as long as you can, wring every last drop out of the game, and then retire and never pick up a bat again in your life?

I’ve been watching Cook for more than a decade, and I’m not really sure. After a while, you learn to stop being surprised by him. Even this century, his first against Australia in seven years and 36 innings, was heavily trailed by the simple fact that he had done very little in quite some time. In a way, this consistent inconsistency, this reliable unreliability, has been the defining trait of Cook’s late career. His last four centuries have come after droughts of 10, 16, 10 and 19 innings. Cook is like one of those giant marine mammals that only needs to eat a few times a year, and so spends most of his time in hibernation, before emerging ominously and menacingly from his lair in search of his next gargantuan meal.

“He’s always had these periods in his career when he might not have scored the runs he wants, then he gets a really big score,” Broad said afterwards. “He doesn’t deal in little hundreds. He seems to go big. You saw the celebrations in the changing room when he got that hundred. They were huge. That’s testament to the bloke he is. He was always going to come good at some stage.”

Cook overcame his struggles on this tour to hit a brilliant century (Getty)

There is no player in the recent history of English cricket - no, not even Kevin Pietersen - who has drawn quite as much unreturned scorn as Cook. With Pietersen, as shabbily as he was treated by those in power, conflict was always innate to his personality, something that drove him, something that he gave back with interest. Cook, for better and for worse, never seemed to to buy into all that. It allowed him to be painted as aloof, arrogant, cold, an establishment stooge - anything you wanted, really. Maybe it was all true. Maybe he quietly relished the battle as much as anyone. But as ever with Cook, we didn’t really know.

What we can tell is how Cook responded. This is the main way in which those at the top of elite sport are not like the rest of us: they may be richer and have slightly better physiques (OK, a lot), but fundamentally the difference is one of temperament. As Broad explained: “I don’t think you play this amount of international sport without some sort of deep, inner self-confidence you can find when things are very low. You have something there that you can clutch onto when things get tough, that hopefully brings you back to performing.”

Cook showed just how much he still has to offer this team (Getty)

Broad was talking about himself as well. This has been a tough tour for Broad too, who came in for especially severe punishment after the mauling in Perth. But he went back to the drawing board, and as James Anderson put it, “worked as hard as I’ve ever seen anyone work at their game”. His reward was four Australian wickets.

Last week Michael Vaughan, a friend of his, was particularly critical, writing that England should consider dropping him for this Test or the forthcoming tour of New Zealand. Broad brushed it off, as you can do after taking four wickets: “Two weeks ago I was on holiday for him, so I don’t know what he’s been saying,” he joshed, and everybody laughed.

Broad's bowling was finally rewarded on Wednesday (Getty)

“I’ve had one of those weeks where you get your tin hat on, duck down and don’t see much,” he said. “You can get yourself in a bit of a dark place if you read everything. People are just doing their jobs. You’ve got to say your opinion, you’ve got to be critical, and I deserved criticism after the Perth defeat, for sure. I’m not going to hold any grudges if people slag me off, because in 15 years’ time I might be doing the same.”