'Etxebe' believes that the 16-year-old is destined for stardom...
Consequently, the experienced Joseba Etxeberria has stated that he believes Muniain is one of the most exciting talents to come through los Leones' youth system for years.
"A footballer of this class integrates themselves very well - football only has one language, and Iker has mastered it," Etxeberria enthused to Radio Euskadi.
"It's very positive news, even aside from his goalscoring contribution to the team. Muniain will certainly be a quality player, not just for this team.
"If he continues along this path, I believe he will become a world class player."
Despite this, Etxeberria gave out a warning to the club's fans. During the summer, Bayern Munich were interested in Fernando Llorente and Liverpool considered a swoop for Javi Martinez, but Athletic managed to hold onto the duo.
The 32-year-old knows it will be even more difficult for the Basques to hold onto Muniain if he surpasses his team-mates' levels.
"We hope he will spend many years here, but this will definitely be difficult," he lamented.
Anthony Wright, Goal.com