Aston Villa winger Trezeguet is being linked with a return to Turkey.
Trezeguet has had an up and down first season in England, with his undoubted highlight the last-gasp winner over Leicester City in the Carabao Cup semi final.
Haber Kartali says he has agreed to a move in principle to Besiktas.
The ex-Kasimpasa man is believed to be keen on a return to the country and has been convinced by Arsenal loanee Mohamed Elneny to make the move to Istanbul.
Elneny is believed to have pleaded with Trezeguet, who has three years left on his Villa deal, on a recent international break.