Former Arsenal captain Cesc Fabregas hailed the performance of William Saliba for victory over Tottenham.
The France defender was outstanding for the 3-1 win.
Cesc said for BT Sport: "That was a fantastic complete performance. I'd like to mention the special name, the fact he was so good he made it look easy is William Saliba.
"I'm sorry but this boy was in France on loan and I was watching him very closely because an ex-Arsenal scout asked me three years ago when we were playing St Etienne in a cup match. I was rested so I was in the stand, he said 'watch this boy, I want to sign him'.
"He was 18, 19 and he was the best player on the pitch so that shows you the potential of this guy, he looks so easy, he could be Arsenal's centre-back for the next 15 to 20 years."