The 2025/26 season confirmed his arrival on the international stage with a house debut at Luzerner Theater as Peter Grimes, performed as part of the world-renowned Lucerne Festival. Critics hailed the portrayal as "a flawless combination of dramatic force and tenor lyricism of ravishing beauty" praising his "boundless vocal resources and commanding presence" and calling him "an artist of the highest caliber." Grimes is a role that demands equal measures of vocal heroism, psychological complexity, and physical endurance, precisely the territory where Mr. Sprague's artistry lives, a singer for whom music and theater are inseparable.

As a member of the ensemble at Badisches Staatstheater Karlsruhe, Mr. Sprague made his debut in the role of Mark in The Wreckers in a highly praised production led by Keith Warner. Other highly successful roles include his portrayals of Lensky in Eugene Onegin and the Chevalier de la Force in Poulenc's Dialogues des Carmélites and the title role in Lili Boulanger's Faust et Hélène, a performance praised for its Wagnerian orchestral and vocal demands. He also performed Lysander in Britten's A Midsummer Night's Dream, deepening a long artistic affinity with the English vocal tradition. As a concert soloist, he has built a parallel reputation for programs of rare ambition and interpretive intelligence, most recently presenting On Wenlock Edge with the Philharmonisches Orchester Erfurt and a solo recital dedicated to twentieth-century English song. Symphonic engagements have included Carmina Burana with the Oslo Philharmonic, reflecting the breadth of a career that moves fluidly between the operatic stage and the concert hall.