MARCELLO Trotta missed a stoppage-time penalty as Brentford blew their automatic promotion hopes in heartbreaking fashion.
The on-loan Fulham frontman smashed his spot-kick against the crossbar in the dying seconds, and Doncaster raced up the other end to snatch a winner and the second promotion spot through James Coppinger to resign the Bees to the play-offs again.
It was cruel on Uwe Rosler's men, who dominated against a Donny side who came and parked the bus.
The visitors had the first sight of goal early on when David Cotterill flashed a shot inches wide of Simon Moore's right post.
But it was Brentford who were a lick a paint away from taking the lead moments later, only for Bradley Wright-Phillips' shot to bounce back off the post.
The Bees dominated possession as Doncaster were happy to just sit back and soak up pressure for the remainder of the half.
Simon Moore done well to parry Coppinger's long-range effort on the stroke of half-time, while the young Bees keeper got down low to deny Cotterill in stoppage-time.
Wright-Phillips was booked for diving when he went down in the box under the challenge of Jamie McCombe at the beginning of the second period.
Jonathan Douglas wasted a glorious chance for the hosts on 65 minutes, blazing over the bar from just inside the box after tireless work from Clayton Donaldson.
Rosler brought on Adam Forshaw, Sam Saunders and Trotta in an attacking switch as time started running out for the Bees.
They were camped inside the Doncaster half in the final stages as they searched desperately for a winner.
Harlee Dean's header was easily gathered by Neil Sullivan, while Saunders' strike was deflected wide.
Brentford were handed the chance to win it at the death when Toumani Diagouraga was bundled over in the box, only for Trotta to fluff his lines from 12 yards.
Doncaster raced up the other end to grab a winner with virtually the last kick of the game as Coppinger slotted into an empty net to clinch promotion.
BEES: Moore, Logan (Forshaw 64), Dean, O'Connor, Bidwell, Douglas (Trotta 76), Adeyemi, Diagouraga, Forrester (Saunders 70), Donaldson, Wright-Phillips.
Subs (not used): Gounet, Hodson, Pierre, El Alagui.
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