The midfielder created his team's second goal and scored their third at St Mary's Stadium as the Saints eased past the Magpies in the Premier League.
"We haven't seen a player like that in this country for a long time," Pochettino told reporters. "Lately he has had a number of opportunities to get into the England national side so that is a very good thing for him.
"I am always telling him that he has the characteristics of a Spanish player and he has the skills of an Iniesta, Xavi or (Cesc) Fabregas.
"Adam is special, he is a very unique player. There is not another player in the country like him."
Southampton continue their Premier League campaign on Saturday when they make the trip to Manchester City.