The Hoops started their Premiership campaign with a 2-1 loss to the Jambos at Tynecastle.
John Souttar scored a late game-winner to undo Anthony Ralston’s equalizer earlier in the second half.
Postecoglou did not name Ntcham in his team of the day for the clash.
And it looks like the French midfielder has returned to his homeland to watch Marseille take on Villarreal in a pre-season friendly.
The 25-year-old posted a video on his Instagram Stories that appears to show his vision of the match from the stands at the Stade Vélodrome.
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He also tagged Marseille stars Dimitri Payet, Pape Gueye and Steve Mandanda in the video.
Ntcham spent the second half of last season on loan with the French giants.
But this decision turned out to be disastrous and led to the departure of André Villas-Boas as manager of the club.
The Portuguese boss went on a rampage at a press conference claiming he had rejected the possibility of bringing in the midfielder.
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Speaking at the time, he said: “It’s a decision I haven’t made.
“He’s a player I specifically said no to. He was not on our list and I have nothing to do with the decision.
“I learned about it when I woke up and saw it in the press.
“I submitted my resignation saying that I did not agree with sports policy.
“The management didn’t give me the last word on things. I don’t want any money, I just want to go. “
Villas-Boas was then sacked from his post following the dispute over Ntcham’s signing and was replaced by Jorge Sampaoli.
However, the Frenchman’s decision only got worse from there as he only made four league appearances.
And he eventually returned to Celtic at the end of last season without having managed to land a permanent contract.
Ntcham appeared set to join AEK Athens last month, but the Greek club pulled out of the deal as the Hoops took a 12-month option on his contract.
In light of this latest development, it remains to be seen exactly where its future lies.
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