The Sun says Shelvey held showdown talks with Rafa Benitez over his role at Newcastle.
The frustrated midfielder, 27, has not started a game since November.
And Shelvey went to Benitez's office last week to ask why he was being constantly overlooked.
The Magpies manager replied by telling the ex-England international he was not fit enough.
But Shelvey questioned how he could be expected to be match fit when he was not given game time.
Following the frank exchange, the ex-Liverpool and Swansea star was an unused substitute in Newcastle's 1-0 win at Leicester on Friday night.
But there are now serious doubts over his future — with West Ham leading the £20million chase to land him this summer.