Newcastle scouted Rangers right-back James Tavernier in Sunday's match with Celtic, according to a report.
The Scottish Sun are reporting that Steve Bruce's side, who are decimated with injury, are 'stepping up their interest' in the star.
While no bid has been made, Rangers are unlikely to welcome bids for their captain at this crucial stage in the season.
The deal would be further complicated by the enmity between Rangers chairman Dave King and Newcastle owner Mike Ashley.
The pair have been involved in several rounds of litigation over the retail deal between Rangers and Ashely's company Sports Direct.
Tavernier started his career on Tyneside but only made nine starts amidst a flurry of loan deals.
He is contracted to 2022 and has been a crucial part of Steven Gerrard's impressive rebuilding of the team.
Newcastle interest was first reported in the summer but Tavernier suggested at the tame that he was focusing on the job in hand at Ibrox.
He said: “It’s a compliment and that is how I see it, but all my emphasis is on Rangers.
“Things can happen in football, but I’m looking forward to this season. It’s all speculation.
“If it stays like that then I don’t get upset about it. I’m fully focused on the job here.”
