Brentford's late, late comeback saw Millwall slip to a 3-2 Sky Bet Championship defeat at Griffin Park on Saturday afternoon.
Tom Bradshaw gave The Lions the lead in first-half stoppage-time - with Bartosz Bialkowski superbly stopping Ollie Watkins' penalty-kick beforehand - before a penalty of Millwall's own, from Jed Wallace, doubled the advantage.
Josh Dasilva halved the deficit with six minutes remaining, with Bryan Mbeumo scoring the equaliser four minutes later. Ollie Watkins then struck four minutes into stoppage-time to secure the win for Brentford.
Caretaker manager Adam Barrett made one enforced change from the 2-1 victory over Leeds United last time out, with birthday boy Shaun Williams coming in for Ryan Leonard. Luke Steele and Jason McCarthy, meanwhile, stepped up to the bench.
Just four minutes in, Brentford had the opportunity to take the lead, but after Said Benrahma's ball snuck behind Millwall's defence, Mathias Jensen's close-range poke at goal was well served by Bartosz Bialkowski. At the other end just seconds later, The Lions had the chance to register the first goal of the afternoon, but Ben Thompson could not make a proper connection on his shot, with the ball eventually cleared to safety.
Benrahma and Rico Henry were proving Brentford's most potent players in the early stages, and the former tried his luck from around 20 yards out with 10 minutes on the clock, but his curler was easily stopped by Bialkowski.
Two minutes later, Millwall's goal led a charmed life - after Jayson Molumby was robbed of possession in the centre-circle, Nikos Karelis' shot looked destined for the net; however, the ball rebounded off the post, hit the prone Mahlon Romeo and rolled into the arms of Bialkowski.
After a period of midfield jostling, the next action of the game came on 24 minutes, when referee Stuart Attwell adjudged Shaun Hutchinson of fouling Henrik Dalsgaard inside the area and gave a penalty-kick. Ollie Watkins confidently stepped up and fired to Bialkowski's left, but the stopper pulled off a magnificent save to keep the score goalless.
The Pole had to stand strong once again shortly after the half-hour mark, stopping Dalsgaard's shot from inside the area, before Jed Wallace's long-range effort was blocked by the Brentford back-line as the closing stages of the first-half approached.
The chances kept coming, as first Jensen's attempt was bravely blocked by Murray Wallace, before Benrahma curled over, but deep into first-half stoppage-time, The Lions took the lead as Bradshaw prodded home from close range after Molumby's shot was parried by David Raya.
Five minutes into the second-half, Brentford had the ball in the net through Watkins, but - eventually - the frontman was ruled to have been in an offside position by a combination of referee Attwell and his assistant.
At the other end, Bradshaw won possession on the edge of the penalty area and looked set to feed Shane Ferguson, but the ball was agonisingly cut out by Jansson and cleared away. With 54 minutes on the clock, Hutchinson was brought down in the box by Watkins, with Attwell pointing the spot for a second time - Jed Wallace stepping and sending Raya the wrong way to double The Lions' lead.
There were 69 minutes played when Brentford, trying to get back into the game, fashioned a chance when Jensen crossed to the back post for Watkins, but he fluffed his lines and the ball went out of play. The Bees were pushing forward as the final 15 minutes came into view, but Millwall's defence were standing firm, with Jake Cooper blocking a shot from Mbeumo.
Jon Dadi Bodvarsson - a replacement for Molumby - ran half the length of the pitch with seven minutes remaining and squared, with the ball eventually making its way out to Ben Thompson, but the midfielder's effort was gathered by Raya, before Dasilva reduced the arrears with 84 minutes gone, striking home from the edge of the penalty area.
Jed Wallace shot over as Millwall looked for a killer third, but it was The Bees who found the net next, with Mbeumo's effort dipping into the top corner on 88 minutes.
Brentford then secured the win four minutes into stoppage-time as Watkins tapped home from close range.
Brentford: Raya, Henry, Norgaard (Dasilva 72'), Jensen (Valencia 81'), Karelis (Mbeumo 45+2'), Benrahma, Watkins, Mokotjo, Jansson, Dalsgaard, Jeanvier. Subs not used: Daniels, Pinnock, Clarke, Zamburek.
Scorer: Dasilva 84', Mbeumo 88', Watkins 90+4'
Booking: Watkins, Mbeumo, Jeanvier
Millwall: Bialkowski, M. Wallace, Hutchinson, Cooper, Williams, J. Wallace, Thompson, Bradshaw, Ferguson, Romeo, Molumby (Bodvarsson 74'). Subs not used: Steele, McCarthy, Smith, Pearce, Mahoney, O'Brien.
Scorer: Bradshaw 45+4', J. Wallace 55' pen
Booking: Hutchinson, Bradshaw, Molumby, J. Wallace, Thompson, Romeo
Referee: Stuart Attwell