Phrygia and other territories had assembled at Zelea, near Dascylium. The two armies met near the river Granicus. Most ancient sources agree that Parmenion advised Alexander not to attack and that it was Alexander's own idea to attack at once.

Parmenion is said to have acted as a foil to his commander's innovative strategies, by expertly formulating the orthodox strategy. For instance, according to Arrian's Anabasis of Alexander, at the Battle of Granicus,