Cassius took his way towards the Euphrates, and succeeded in escaping with 500 horse.
Octavius, with a division which is estimated at 5,000 men, reached the outskirts of the the hills at a place called Sinnaca, and found himself in comparative security.

Crassus, misled by his guides, made but poor progress during the night; he had, however, arrived within little more than a mile of Octavius before the enemy, who would not stir till daybreak, overtook him.

Pressed upon by their advancing squandrons, he, with his small band of 2,000 legionaries and a few horsemen, occupied a low hillock connected by a ridge of rising ground with the position of Sinnaca.

Here the Parthian host beset him; and he would infallibly have been slain or captured at once, had not Octavius, deserting his place of safety, descended to the aid of his commander.

The united 7,000 held their own against the enemy, having the advantage of the ground, and having perhaps by the experience of some days learnt the weak points of Parthian warfare.
Surenas was anxious, above all things, to secure the person of the Roman commander.