Lewis Grabban's penalty in first-half injury-time was his fifth goal of the season
Brentford came from 3-1 down at the break to deny struggling Sunderland a second Championship win of the season.
The Black Cats had only picked up four points from their past 10 matches and trailed to a Nico Yennaris tap-in.
But Lewis Grabban struck an equaliser, Bryan Oviedo's corner was fumbled in by keeper David Bentley for number two and Grabban's penalty made it 3-1.
Florian Jozefzoon's stunning effort got the Bees back in the game and Neal Maupay's deflected shot earned a point.
The Black Cats would have climbed out of the relegation zone with a win and appeared set to do so when they went 3-1 ahead in a breathless first league meeting between the two sides since the 1992-93 season.
Yennaris' two-yard effort after Jozefzoon's shot hit the post simply sparked Sunderland into life.
Grabban's neat low strike into the corner and cool spot-kick after Bentley's own goal seemingly put them in control.
But the Bees created opportunities throughout, managing 18 efforts on goal, and Jozefzoon smashed in a superb second home goal soon after the interval.
With Sunderland also struggling to retain possession, Brentford got the equaliser they deserved.
Maupay struck the crucial goal, following good work by the impressive Jozefzoon, but it needed a big deflection on its way into the net.
Brentford manager Dean Smith:
"I was angry at the break and I am still angry now because we gave them three goals. I can't remember them creating any chances apart from the ones we gave them.
"It was very windy and stop-start so we couldn't get any rhythm in the game but that was no excuse for the goals we handed them, which were all the result of individual mistakes.
"We got to half-time and I didn't need to talk tactics with them, but individually we needed to be better with the football.
"I'm pleased they showed me a response even though I couldn't celebrate our second goal as I was still too angry. If we have ambitions to be a top-six side in this league then we need to turn games like this into three points."
Sunderland boss Simon Grayson:
"We were playing quite well so not to win is frustrating and disappointing, but it was one of those games where we might have taken the point beforehand. That said, when you are in the position we were you want to go and win it.
"Their second goal came from a free-kick which we thought was a good tackle from Didier Ndong but we defended well, got back into it and then the deflection allowed them back in.
"We defended well and had a good shape. You have to defend well against Brentford and for large parts we did. We were decent going forward but we still have to put a few more of the ingredients together. There were signs that we are looking like a decent team.
"We are three games undefeated and we are making progress. We've now got back-to-back home games to build on that, so this performance and the character we showed will give us a lift."
