Goikoetxea played with Koeman at Barca and is confident he's the right man for the Nou Camp at this time.
He told Marca: "Koeman in the locker room was one of the biggest weight. He has a lot of character.
"He has made many decisions this summer."
Goikoetxea admits he's a fan of Ansu Fati.
"Ansu Fati has been a real discovery. His appearance has been brutal. He has a lot of self-confidence. You have to be patient because they are going to push him more and more."