Han Chinese defeat Roman legionaires 36 BC?

[FAVENTIANVS]

I've read such episode in Mario Brusagli's ATTILA, being those Roman soldiers ex prisoners from the Parthians, and because of a Parthian costume to keep captured enemy military organization and structure within the prisoners to increase its humiliation and to keep some order.
It also says that these legionaries could come from both Crassus or Marc Antony's defeated armies, then transferred to the far east of Persia (to stay afar from the temptation to scape back to Roman territory) and then, under a Hsiung-nu raid (scaping from the Han) freed and entered as the Chi-chi bodyguard getting back their military dignity and position.

Johnny, are you preparing a picture of this episode? WOW!!!