Ronald Koeman could tell Zlatan Ibrahimovic was "a fantastic player" when he joined Ajax as a teenager.
Ibrahimovic will look to condemn Koeman's Everton side to defeat on Sunday when Manchester United visit Goodison Park.
The Swede has 11 goals in all competitions in his first season at Old Trafford, joining United in the close-season having won league titles in Netherlands, Italy, Spain and France.
It was with Ajax that he won his first major honours, helping them to two Eredivisie crowns after making the move from Swedish side Malmo as a 19-year-old in 2001.
Koeman oversaw both of those league title wins and the early stages of Ibrahimovic's development and, speaking at his pre-match media conference, said the striker's quality was immediately obvious.
"Already at 19 you saw a fantastic player," Koeman said of Ibrahimovic.
"He is one of the best players. It’s the last part of his career but he is still motivated and scoring goals.
"If he looks back then he can be very proud about what he showed and what he was winning.
"He is the type of football player you like to have in your team. It was nice to work with him.
"He was young and sometimes difficult for the manager, but I enjoyed working with him."