sentences:  The same year, O'Neill made his role debut as Walter von Stolzing in "Die Meistersinger von Nürnberg" at Covent Garden.His performances have included; the title roles of "Parsifal", "Lohengrin" at the Royal Opera House with Sir Antonio Pappano, "Otello" and "Lohengrin" at Houston Grand Opera, the title role in Verdi's "Otello" and Sergei in his Opera Australia debut in "Lady Macbeth of Mtsensk", Florestan with Daniel Barenboim at the BBC Proms with the West-Eastern Divan Orchestra and made his Carnegie Hall debut as Caesar in Samuel Barber's "Antony and Cleopatra" for New York City Opera, returning with the Metropolitan Opera Orchestra and James Levine for Mahler's "Das Lied von der Erde" and sang in Beethoven's "Missa solemnis" with the Boston Symphony.O'Neill is the patron of the New Zealand Association of Teachers of Singing (Newzats), the New Zealand Singing School, New Zealand Opera Circle 100, the New Zealand Brass Foundation, the Auckland Boys' Choir, the Ashburton MSA Choir, the Christchurch City Choir and the UK Singingworks.