Alexander Isak's future at Newcastle hangs in the balance after the Swedish striker was reportedly told to train apart from the rest of the squad on Wednesday.
The 25-year-old has been linked with a British transfer record move to Liverpool after failing to feature in Newcastle's pre-season preparations.
Isak missed the Magpies' trip to Singapore and South Korea, citing a minor thigh injury, and instead flew to Spain to train at former club Real Sociedad.
He has since returned to Tyneside but Sky Sports reported that Isak was instructed to train after the rest of the squad had departed on Wednesday.
"You have to earn the right to train with us. We are Newcastle United," manager Eddie Howe told reporters earlier in pre-season.
"We will make sure that any player earns the right to train with the group. No player can expect to act poorly and train with the group as normal."
Liverpool have seen a £110 million bid for Isak rejected, according to reports, with Newcastle seeking closer to £150 million.
Another major hurdle to any deal is Newcastle's ongoing struggles to finalise a deal to replace Isak.
They face competition from Manchester United for RB Leipzig striker Benjamin Sesko after missing out on Joao Pedro, Hugo Ekitike and Liam Delap earlier in the window.
Liverpool have already splashed out over £250 million this window on Ekitike, Florian Wirtz, Milos Kerkez and Jeremie Frimpong.
However, they have also recouped major funds from the sales of Luis Diaz, Jarell Quansah, Caoimhin Kelleher, Trent Alexander-Arnold and Tyler Morton.
And Darwin Nunez is close to a £46 million move to Saudi side Al Hilal that would free up more resources and space in the squad for another bid to sign Isak.
Since joining Newcastle for £63 million in 2022, Isak has scored 62 times in 109 appearances, including the goal that secured the club's first domestic trophy for 70 years in the League Cup final against Liverpool in March.