The winger rose highest at the far post to guide Tommy Smith’s clever cross past Karl Darlow to keep the Bees in the Sky Bet Championship play-off places.
A point looked unlikely with 10 minutes to go after Tyler Walker and Todd Kane had given the visitors a two-goal cushion.
Walker struck first on the hour mark as he capitalised on a James Tarkowski slip to drill a sizzling low drive past David Button at the near post.
Kane stretched the lead with just a quarter of an hour remaining with a quick counter attack that left Brentford reeling.
Darlow fed Ben Osborn wide on the left and his diagonal ball to the far past was coolly converted by Todd Kane at the back post.
But the Londoners hit back with 10 minutes remaining, Andre Gray turning on a sixpence to send a rasping drive past Darlow and into the bottom corner.
The draw was no more than Mark Warburton’s side deserved after they dominated possession and forced Darlow into a string of good stops after the break.
But Michail Antonio’s physical presence was a constant threat for the visitors and caused Tarkowski and Harlee Dean problems all afternoon.
Brentford could have taken the lead on 24 minutes when Gray’s goal-bound volley was blocked at point-blank range by the head of David Vaughan.
Darlow came to Forest’s rescue just before the half-hour mark when he slipped as he set to clear Kelvin Wilson’s back pass, but he just managed to get enough on the ball to clear.
Skipper Jake Bidwell fizzed a low drive just wide after Gray forced a full length save from Darlow when he was played in cleverly by Moses Odubajo.
But Forest should have gone in at the break a goal to the good after Antonio forced his way past Odubajo and teed up Walker, who sliced wide with the goal gaping.
After the interval Forest sat back and were happy to play on the break, as Brentford surged forward in waves looking to get a foothold.
But the tactic backfired after Pritchard’s dipping low drive was saved and Darlow earned an assist for the visitors’ second.
Jota, Pritchard, Judge and Gray all went close for the hosts and were rewarded when Gray scored a typical opportunist striker’s goal when he turned and shot in one movement to leave Darlow grasping thin air.
Forest were playing on the edge of their box by now but an equaliser still looked unlikely as they defended resolutely until Smith used his experience to carve open the away defence for a crucial point.
His far-post dink was nodded home by Jota – also on the scoresheet in stoppage time in the Good Friday rout of Fulham – who is fast earning himself a cult status at Griffin Park.