Answer
The answer is Iker Casillas. As one of the most exceptional goalkeepers of all time, Iker Casillas has had a profound impact on Marc-André ter Stegen's career. Ter Stegen greatly admires Casillas's outstanding shot-stopping abilities, command of the penalty area, and exceptional leadership qualities. Casillas' influence on ter Stegen's goalkeeping style and development is evident in the latter's performances for both club and country.