On his return to London Nash was engaged by the Old Vic Company under Lilian Baylis to sing tenor roles in English. His first part for the company was the Duke in "Rigoletto". His success was instantaneous. "The Musical Times" said that it was a pleasure to welcome a very beautiful tenor voice, praised his clarity of diction, and predicted that Nash would be one of the eminent lyric tenors of the future. At the Old Vic he appeared as Tonio in "The Daughter of the Regiment", in the title role in "Faust", as Pinkerton in "Madama Butterfly" and as Tamino in "The Magic Flute". At the end of the Old Vic season he joined the British National Opera Company, going on tour with the company after a short London season. His roles included Almaviva, Fenton in "Falstaff", Turiddu in "Cavalleria rusticana", Roméo in "Roméo et Juliette", Des Grieux in "Manon" and David in "Die Meistersinger von Nürnberg".