Signorelli and movement
In 1498 Luca Signorelli left Città di Castello where he had dominated the artistic scene. This left the way open for Raphael to make his mark on the city. The artists certainly knew each other, and Signorelli may even have introduced Raphael to patrons there.
Whilst working on his own commissions Raphael carefully studied Signorelli's altarpieces in the city, including 'The Adoration of the Shepherds'. From Signorelli, Raphael learnt how to paint the male nude in action, giving it swagger and movement and he also learnt foreshortening.
Raphael's drawings in black chalk from this date are so close to Signorelli's that it is likely Signorelli gave him access to his own drawings.