The Sun says Ba has a clause in his contract stating he can go if a club offer £7.5m - but £2.5m of that will go to the player himself.
That leaves Toon boss Alan Pardew with virtually nothing to spend on a top-class replacement.
Ba, 27, has resisted all efforts to get him to sign a new deal which would scrap that £7.5m clause.
And his main reason for rejecting Toon's offers is that agreement in his current deal which entitles him to the £2.5m pay-off.
Now Pardew is resigned to losing 11-goal Ba when the transfer window opens next week.
Arsenal, QPR and Paris St Germain are all keen on the Senegal hitman, who joined Newcastle on a free transfer from West Ham 18 months ago.