The 28-year-old is out of contract at the end of the season and has turned down a new deal, sparking suggestions that Pool could look to cash in on him during this month’s transfer window.
But manager Grayson said: “People are going to put two and two together and think Jordan arriving means Curtis is going out. That’s not the case at this moment.
“Curtis’ contract situation has been talked about. It’s stalled and stopped because it didn’t suit both parties. We’re comfortable with that and he is.
“Just because he has four months left of his contract and we’ve signed Jordan shouldn’t mean that he’s leaving.
“Do I think he’ll still be here? Who knows? You’re asking me questions I don’t know the answers to.
“Every player has a price on their head, whether that’s Curtis, Callum Guy, Calum Macdonald or whoever.
“We need centre-backs to add to the competition as Rocky Bushiri has been recalled to Norwich and has gone out to Belgium on loan (signing for Sint-Truidense). We thank him for the bits he did for us. It didn’t quite work out, that one.
“But we’re doing plenty of work behind the scenes to improve all over the pitch, which we know needs to be done.”
Tilt impressed on a rare start in Saturday’s FA Cup draw at Reading, where he replaced Ryan Edwards and looked out to prove a point.
“So he should,” added Grayson. “Anybody who has been out of the team and then gets an opportunity has to show what they’re capable of. Curtis did really well and that’s what we want – competition for places.”
Another centre-back Pool could lose in this window is Ben Heneghan, whose loan deal expires next Tuesday.
The Seasiders would like to sign the 26-year-old from Sheffield United on a permanent basis but face competition from Luton Town.
Grayson repeated his stance that Thorniley was brought in to add depth to the squad and not to replace Heneghan or Tilt.
“It’s more about competition for places,” the Pool boss added. “Anything off the back of it we’ll deal with and see where it takes us .
“Nobody has left the building. Is anybody leaving the building soon? Who knows? I haven’t got a clue. I’m not a mind-reader.
“Jordan is here first and foremost to add competition to the squad that we feel is going to help us and make us better.”