The reigning French champions have spent much of the summer chasing the Brazilian teenager's signature.
They would appear to closing on his capture, with the 19-year-old centre-back all set to put to paper.
Blanc believes a transfer could be pushed through before the weekend, with Marquinhos due to undergo a medical in Paris on Friday.
Should those physical examinations uncover no cause for concern, an agreement which is reported to be worth around €35million (£30m) will be tied up.
Blanc said: "He is young, very talented and with great potential.
"It's a dossier that's been going on a long time and will come to fruition this afternoon (Friday), I hope.
"This proves that PSG are also recruiting for the future, he offers us a certain guarantee for the future."
PSG have already acquired the services of Lucas Digne from Lille and Edinson Cavani from Napoli during the current transfer window.