In the Iliad, the battle often appears to be between individual heroes and it is left to your imagination what the general mass of soldiers are doing. Later Greek warfare depended on the phalanx being unbroken and there is some hint of this in the Iliad.
ὦ φίλοι ἀνέρες ἔστε καὶ ἄλκιμον ἦτορ ἕλεσθε,
ἀλλήλους τ᾽ αἰδεῖσθε κατὰ κρατερὰς ὑσμίνας:
αἰδομένων ἀνδρῶν πλέονες σόοι ἠὲ πέφανται:
φευγόντων δ᾽ οὔτ᾽ ἂρ κλέος ὄρνυται οὔτε τις ἀλκή.
My friends, be men and take a valiant heart. Have respect for each other in the hard battle for when men respect each other more are saved than killed. But for men who run away there is neither glory or any safe defence.