The Colombian centre half has experienced a mixed campaign with the Toffees.
As his contract expires, Mina may be about to leave the club where he has played since 2018.
"He has been a fantastic servant," Pickford said when asked about Mina, per the Liverpool Echo.
"He is a top player. He came from Barcelona, Colombia international, and he is a great lad.
"He came over and had to learn English. He's brilliant and a great character in the dressing room, but when he stepped over that white line, he gave absolutely everything.
"Injuries have probably stopped him in his tracks. For us, we have just got to keep going, but Yerry has been a top lad and a top servant to the club."