Adrien Broner -- Got 3 Flashy Victory Chains ... On Night of Loss

Adrian Broner REALLY thought he was gonna win that fight against Shawn Porter last weekend ... which is why he dropped $120k on diamond chains to be delivered to him right after the bout.

The bad news ... Broner lost the fight.
The good news ... he still got some pretty awesome jewelry.

Sources tell TMZ Sports ... Broner hit up Avianne and Co. in NYC and ordered three $40k chains (that weight 100 grams each) which each included diamond encrusted AB pendants.