According to the Mirror, Zarate slammed his then Hammers boss saying Big Sam had refused to play him because he was signed by Hammers co-owner David Sullivan.
Allardyce claimed that was "not true" and told BBC Sport at the time: "I base my feelings on what I consider to be the best team. It's a professional, clinical decision, not an emotional one," Allardyce said.
It looked like Big Sam was right too when Redknapp tried to send Zarate back to West Ham before he had even kicked a ball for the R’s.
But the past is irrelevant to Bilic who has hinted that characters like the skilful attacker, who has two years left on his West Ham contract, are what a club like West Ham needs.
"If you want to be successful you can’t have just one way of playing," Bilic told the Daily Mail.
"You need organisation and also flair players.
"Every manager would love players who will nod at whatever you say. But to go to an away game in front of 60,000 people booing, you have to be special.
"If he is strong on the pitch, he is strong off the pitch. I like those characters."
It had all started so well for Zarate in East London after his move from Argentinian side Velez Sarsfield when he scored a sublime volley in a 3-1 win at Crystal Palace on back in August last year.
But he was in and out of the side after that scoring just once more, away at Everton.
Zarate has 84 goals from 283 career games and many fans still feel the diminutive star is yet to be given a fair crack of the whip at West Ham.
They will have to wait and see if having the more attack-minded Bilic and starting with a clean slate helps get the best out of the star.