Complex sentence: At English National Opera, he commissioned film director Anthony Minghella's opera debut, Madam Butterfly, which subsequently opened the 2006/7 New York Metropolitan Opera season, the first time in that company's history they had opened a season with another company's work.
Split into simpler sentences: At English National Opera, he commissioned the film director Anthony Minghella's opera debut, "Madam Butterfly". It subsequently opened the 2006/7 New York Metropolitan Opera season, the first time that the company opened a season with another company's work.