In this masterful study, a preparatory drawing for two of the leading warriors in The Battle of Anghiari fresco, Leonardo exploits the chalk or charcoal medium in order to achieve maximum force of expression, smudging the parallel hatched lines in order to create a seamless, blended sfumato, or “smoky”, effect in the rendering of shadows.

The vigour of the main figure is perfectly captured by the technique, with the deep, incised lines of the face forcefully delineated using the sharp point of the chalk.

This figure – a screaming soldier seen in three-quarter view, facing right, is usually thought to represent Niccolò Piccinino, the condottiere in command of the Milanese troops of the Duke Filippo Maria Visconti, who were defeated by the Florentines. The profile is a study for one of the soldiers to his right.

The lack of definition of the upper part of both heads probably relates to the fact that in the final design the figures would have been portrayed with headgear.