Olympiacos officially announced that they have signed Spanish head coach Imanol Alguacil, who will take over the team from the respected former manager Mendilibar.

Imanol Alguacil Barrenetxea was born on July 4, 1971, in Orio, Gipuzkoa, and came through the Real Sociedad youth academy. Alguacil joined Real Sociedad's first team in the summer of 1991 and left the club in 1998 to join Villarreal. After that, Alguacil also played for teams including Jaen, Cartagena, and Burgos. In the summer of 2003, Alguacil announced his retirement after leaving Burgos.
After hanging up his boots, Alguacil began his coaching career with the youth team of his hometown club Orioko, and later also coached Zarautz's youth team. In the summer of 2011, Alguacil left Zarautz and returned to Zubieta, where he coached several levels of Real Sociedad's youth system.
In March 2018, then-Real Sociedad head coach Eusebio Sacristan was dismissed, and Alguacil, who was then in charge of Real Sociedad B, took over the first team and led them through the remainder of the season. He later returned to coach Real Sociedad B. In December of the same year, then-Real Sociedad head coach Asier Garitano was dismissed, and Alguacil officially became the head coach of Real Sociedad's first team.
In April 2025, due to fluctuations in the team's results, Alguacil voluntarily declined to renew his contract and left Real Sociedad.
In July 2025, Alguacil took charge of Saudi club Al Shabab, and he was dismissed by Al Shabab in February 2026.