Technically demanding and at times furiously paced, two newly identified Mozart works unveiled Sunday are helping scholars complete their assessment of the maestro's very early achievements. The childhood creations — an extensive concerto movement and a fragmentary prelude — provide yet more proof the Salzburg native was a true prodigy. And maybe a bit of a showoff.

Leisinger said Mozart likely wrote the two newly attributed pieces when he was 7 or 8 years old, with his father, Leopold, transcribing the notes as his son played them at the keyboard.

A series of analyses confirmed the writing as Leopold's; at the time Mozart was not yet versed in musical notation. But Leopold was ruled out as the composer of the pieces based on stylistic scrutiny, the Mozarteum said in a statement.