[quote=Herzinth]
Barristan Selmy < Lord Beric < Ser Davros
[/quote]

Lord Beric loses to a fight against Selmy hands down. 

There's like three tiers of fighter in ASOIAF. Beric is tier 2. 

Selmy is tier one.

The only people who could defeat Selmy would be Season 1 Jaime Lannister and Arthur Dayne. And the fight between Selmy and Jaime would be close but I give it to Jaime (and Jaime even says himself) that he would him because of his youth.