Rangers and Celtic are both plotting a move for 6ft 4in centre-back Jarrad Branthwaite, according to the Scottish Sun.
Both clubs have been scouting the 17-year-old since he burst into the Carlisle first team this season.
He spent the first 13 league games of the season on the bench but has started the last six and played 90 minutes in five of them.
Rangers are plotting a move in the January window after sending one of their top scouts down to watch him.
Carlisle are under no imperative to sell though, with the player in contract until 2021 and they have the option of another year on the youngster.
All the attention seems to be having an effect on the player, who missed the FA Cup game against Forest Green at the weekend with a virus.
Talking in the News & Star, Carlisle boss Chris Beech said, “He [Branthwaite] has had a massive period before I’ve come – he’s getting a lot of media attention and quite right, and it’s very difficult as a young player to receive that and keep going.
“They’re human beings, it’s the first time it’s happened to him in his life, and he’s ended up picking a virus up.
“I was told he was ill on Friday of last week but didn’t tell anybody, played against Cambridge and he’s really plummeted in terms of his immune system.
“The doc and Dolly [Neil Dalton] the physio are picking him up.”
Rangers are well-staffed in the centre of defence after George Edmundson and Filip Helander arrived in the summer.
Helander has formed a good partnership with Connor Goldson, with Nikola Katic in the mix too.
In other Rangers news, ‘Very sharp’ – McNamara drools over Rangers ace who is getting ‘stronger’