Vazirabad eventually stamped his class on the Qatar Prix du Cadran at Chantilly.
A dual winner of the Prix Royal-Oak at Saint-Cloud and runner-up to the Roger Charlton-trained Quest For More in this Group One event a year ago, Alain de Royer-Dupre's star stayer appeared to face a relatively straightforward task following the withdrawal of Michael Bell's Gold Cup hero Big Orange.
Christophe Soumillon took his time aboard the 1-6 favourite before angling him wide in the straight and asking him to chase down Mille Et Mille.
Just for a moment it looked as though it could be a close call, with Vazirabad lugging in behind the leader once coming under pressure, but he asserted close home and was ultimately well on top.
Mille Et Mille was a long way clear of the rest in second.
In Big Orange's absence, the only British-trained contender was Tim Easterby's High Jinx, who finished fourth.
De Royer-Dupre confirmed Vazirabad will now bid for a hat-trick in the Prix Royal-Oak on October 22, with British racegoers set to get the chance to see him in the flesh next season.
"That is him - he only does just enough, which is why he could have a long career," said the trainer.
"He was injured two races ago and was stuck for a month, but he is good now.
"I think, in this kind of ground, it could be easier to have beaten Big Orange.
"Next year he could have two options - Ascot (Gold Cup) and Goodwood (Cup) - but it depends on how he is and what the ground is like."