https:// www.photo-mark.com/funhouse/chess/

This webiste runs through the entire marshall capablanca match.

When you get to the board that looks like julian’s it talks about pawn strategy and says:

A pawn who has escaped the confines of his opponenent is one of the most dangerous threats to the endgame.

Folks, julian is a promoted pawn and he’s going to help finish the game!