Gyasi currently plays for the Cobblers Under-11s as a striker and has been with the club's centre of excellence for the last three years. And he has caught the eye of the Premier League champions, with the fee potentially rising due to several clauses in the deal.
Head of the centre of excellence Trevor Gould said: "Not only is this is a superb opportunity for Michael but it reinforces the quality of player we are bringing both into the club and through our centre of excellence.
"Michael has progressed well and has improved with our coaching, and while we obviously want to produce and keep our best players, when a Premier League club like Chelsea come knocking then as long as the deal is right for the club, we will never stand in a boy's way.
"It would not be fair on them or their parents to do so. That is the understanding we have with all of our boys, and that trust helps us attract the best local players to the club."