New Boro boss Garry Monk is keen to bolster his attacking options to help fire the Teesiders back into the Premiership.
Burnley have challenged Boro to the signature of the £15m rated Assombolanga.
But Monk has already listed his back up option in the 27-year old Gayle.
The former Crystal Palace striker scored 23 goals for the Magpies last season.
And Boro could test Newcastle's resolve by offering £10m for the Englishman.