Chelsea centre back Malang Sarr, who joined in the summer from Nice, is close to agreeing his proposed loan move to Porto.
The 21-year-old impressed with his boyhood club in France, having made 119 appearances for the club, and earned his move to Chelsea on a free transfer.
Sarr can also play left back and will help fill the void left by Alex Telles who is joining Manchester United for £15.4m on a five year contract.
It is expected he will officially put pen to paper for the season-long stint on deadline day.