Celtic could see a pathway open up to sign two of their targets - with Mika Baur's manager conceding he could leave and Haissem Hassan reportedly rejecting another offer.
Parkhead chiefs have held discussions with Paderborn over central midfielder and have reportedly already had an offer of £4 million rejected, with talks ongoing.
The Germany under-21s star has a contract until next summer and Celtic seem confident of agreeing a deal in this window.
The Bundesliga new boys' boss Ralf Kettemann had previously cooled speculation over Baur's future but has now said he would be relaxed should he move on.
He told Kicker: "We have good players internally and also good ideas in case something happens. So I'm relaxed."
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Meanwhile, it is claimed Egypt winger Hassan has turned down a lucrative offer from Saudi Arabia.
The Scottish champions had the 24-year-old on their radar as he shone at the World Cup over the summer, but other clubs are also interested.
Indeed, Spanish outlet La Nueva Espana claims the Real Oviedo star has been the subject of a bid from the Saudi Pro League, one which he has turned down.
The report suggests the wide man was offered a five-year contract worth £2million per year.
However, it is believed he only wants a move to another European club.
