SOLVED. Historical fiction in Roman times - possibly YA? [s]

[Jiggy]

All I can recall about the book:
- the main character is a boy (maybe early teens) whose father is a soldier in the Roman (?) army; the father is killed during a raid by the enemy
- the boy is injured I think on the shoulder or arm, bad enough he can't enlist in the army
- boy's injury is "repaired" by a man who had been exiled for treason
- there are papers exonerating the man but his enemy holds them
- the boy meets Emperor Hadrian in a bathhouse, finds out his friend can't be pardoned without evidence
- boy steals evidence from the enemy's home by swimming across a moat or river

I read this book 10 years ago, and even with all the details I remember I've never found the book. Hopefully one of you recognizes it!

[Tab]

The Eagle of the Ninth fits a little.

Do you remember the cover?
Part of a series?

[Jiggy]

Series - not to my knowledge. It was written very much like a stand alone. And I vaguely remember a blue cover with a face on it?

[Rachel]

This sounds like Word to Caesar. His father is killed, he's injured, he meets a guy named Lucius who has been exiled and so the boy goes to meet the Emperor to get the exile repealed.

[Jiggy]

This is it! Thank you so much!!!!