What a versatile master is the Royal Opera’s resident dynamo Antonio Pappano. On Saturday night, he was in the Covent Garden pit getting big-band sounds and tender elegies from the whole orchestra in Turnage’s Anna Nicole. And here he was again, moving from a surprisingly fine score to a great one, the shadow-of-mortality approach to Chinese poetry that is Mahler’s Das Lied von der Erde, albeit in its ingenious chamber reduction by Schoenberg. Oh, and with the small detail of a mezzo’s ultimate challenge being faced by a baritone.