Isak is among a number of Newcastle stars understood to have clauses in their contract reducing their wages if they do not qualify for the Champions League.
The Swede’s current deal expires in the summer of 2028 but speculation has intensified over this future following a superb season for Eddie Howe’s side.
The clause was inserted into the contract of Newcastle’s playing staff by former sporting director Dan Ashworth, who is on Gardening leave ahead of a move to Manchester United.
Isak is one of the players affected and could lose up to 20 per cent of his wages.
However, the Magpies are ready to thrash out a new deal with the Swede that could see a dramatic rise in wages, putting him on par with top earner Bruno Guimaraes.
Newcastle appear to have left it too late to qualify for next season’s revamped Champions League and missing out could have repercussions for the Magpies.
Barcelona and Arsenal have both been linked with the £63million striker in recent weeks with Champions League football on offer as part of their bargaining chip.
Both sides are in need of a striker with Barca reportedly ready to part ways with 35-year-old Robert Lewandowski, while the Gunners may look to cash in on Gabriel Jesus who has netted just four league goals this season.
While the Magpies would be reluctant to part ways with the 24-year-old, it is understood they value the striker at around £90m.
That would pose a problem to the cash-strapped Catalan’s who would need to offload multiple saleable assets before entering any tug-of-war with Arsenal.
Isak has been hampered by injuries since arriving on Tyneside from Real Sociedad in August 2022.
This season alone, the Swede has missed two months of action after sustaining multiple groin injuries.
His 21 goals in 34 games this term makes for impressive reading having spent a substantial period in the treatment room.
Isak is in the running for this season’s Premier League Golden Boot award thanks to his 17 goals so far.
The Swede has six games left to stake a claim for the prize and is currently three-goals adrift of joint-leaders Erling Haaland and Cole Palmer.
Aston Villa’s Ollie Watkins and Bournemouth’s Dominic Solanke are also in the race for the Golden boot having registered 19 and 18 goals respectively.
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