Sourav head is not something to be invaded without careful consideration of the likely consequences. There aren't many lessons that journalists can teach cricketers, but that is one of them.
South Africa discovered this truth the hard way at Newlands on Wednesday after Dale Steyn — a feisty little fast bowler who appears to be made entirely of sinew, gristle and bone — paid Ganguly the compliment of cracking him on the head with a bouncer.
It was the third ball that Ganguly faced, and it struck him as surely as a wayward insect meeting its messy end on a windscreen. Ganguly, clearly rendered groggy by the awful blow, removed his helmet and examined it intently. The minutes ticked by as he tried to bend the grille back into shape. Eventually, he gave up and called for a new hardhat.
Ganguly defended Steyn's next ball comfortably enough. Then he dug out a yorker. And then, his head having cleared, he rocked onto the back foot and jabbed a boundary through the covers.
That was the first of nine fours Ganguly would hit, and he also arched Paul Harris, the debutant left-arm spinner, over long-on for six.
More than that, Ganguly did what Ganguly does best: he looked within and found what India required of him. He knew, for a start, that his team would need him to bat at number six.
Virender Sehwag had been pencilled in at the pivotal position, but if whispers from the dressing room are to be believed, Ganguly stood firm that he was the man for the job.
He was given his head, and he kept it while almost all of those about him were losing theirs and, with that, their wickets. Ganguly may have reached his 39th half-century with a breathless edge through the slips, but there was no doubting the authenticity of his effort.
There never has been. Ganguly is capable of generating myriad emotions in his supporters as well as in his detractors. He delights us, infuriates us, demands our respect, earns it, and refuses to come down to our level. Quite often he does all this, and more, in the space of a few frenetic overs.
But no one has yet had cause to doubt his commitment to the Indian team, nor his own bedrock belief that India need Ganguly more than most others.
You could call that arrogance, or evidence of delusion, or you could even label it destructive.
Some of us, however, will continue to call it genius.