In the simulation of the battle of Nájera the center of gravity of both maneuvers (defensive and offensive) will be the Nájera Bridge over the Najerilla River. The French and Castilians will have the opportunity to force the English into a disadvantageous attack, as the Scots succeeded and won at the Battle of Stirling Bridge. French and Castilian employment will be tested for a Concave or Italian Defense battle order, which has its best job in the situation where a defense initially gives up, with or without intention, its center. Comparable to an Italian Opening in Chess.