How does strength of boric acid solution increase in presence of salicylic acid? A while ago, I read that salicylic acid can make boric acid solution strongly acidic when it's added to it. 

To my knowledge, I know that boric acid becomes a strong acid in presence of cis-diols (except ethylene glycol). I also know that it happens due to increased stability of conjugate base by chelation using polyhydroxy compounds. 

But I can't really make out the case with salicylic acid. I will be really thankful if you could shed some light on this topic.
Equilibrium will be far to the right, as a stable six membered ring is formed. The proton speaks for itself.



References: Queen, A. The kinetics of the reaction of boric acid with salicylic acid. Can. J. Chem. 1977, 55 (16), 3035–3039 DOI: 10.1139/v77-421.