Celtic have made a £3.4million (€4m) bid for Bologna's Aaron Hickey, according to a report.
The teenage left-back is a former Parkhead academy prospect but left the club in 2018 to join Hearts.
Hickey became a breakthrough star at Tynecastle, making his debut aged just 16 and later sealing a sensational £1.5m move to Serie A.
The 19-year-old has long been linked with a return to Celtic and speculation has intensified following the appointment of Ange Postecoglou as new manager.
And now il Resto del Carlino report the Glasgow giants have firmed up that interest with an opening offer.
Last week, Bologna's league rivals Napoli were urged to make a move for the Scot.
Their former manager Gianni di Marzio now works for the club as a transfer consultant and he believes signing Hickey would be excellent business.
He said: "Napoli need to make some serious changes to their team for the new season. They have to get rid of players and recruit well.
"I'm looking at someone like Aaron Hickey of Bologna - I see him as being a perfect fit for Napoli.
"Hickey is a very good, young player. He knows how to do both the defensive side of the game and he's very dangerous in an attacking sense.
"Of course, it would depend on how much he is available for and how much Napoli wants to invest, but he has to be someone that would interest them.”
Hickey is due to report for pre-season training with Bologna after recovering from a shoulder operation.
