Tyler Walker's first professional goal and Todd Kane's strike had put Nottingham Forest two goals to the good with just over ten minutes remaining.
But Brentford showed their desire to reach the play-offs by netting twice in a frantic finale, Jota's equaliser timed at 94 minutes.
The hosts had a whopping 33 shots during the match and were the dominant side but the Reds showed plenty of battling spirit despite their season being all but over.
Dougie Freedman was unhappy, however, with what he called 'naive' defending from Forest as Brentford pushed forwards towards the end of the game.