Brentford's trip across London to Leyton Orient ended in disappointment as they slumped to a 2-0 defeat at the Matchroom Stadium on Saturday.
During a lethargic display the Bees found themselves two goals down by the half time interval and despite boss Uwe Rosler making two changes at the break, never came close to hauling themselves back into the game.
The first real chance fell to Orient when captain Matthew Spring headed a Jamal Campbell-Ryce cross from the right over the bar.
Orient then thought they had taken the lead when Dean Cox's deflected shot cannoned off the post and was steered home by the offside Jimmy Smith.
Brentford should have taken the lead when Orient's keeper Paul Rachubka spilled Niall McGinn's shot from the right and Saido Berahino shot wide of the left hand post with the goal at his mercy.
Adam Forshaw then had a chance to break the deadlock when he fired a 30 yard free kick just wide of the left hand post.
The Bees were undone after half an hour when Cox whipped in a free kick from the left and Kevin Lisbie reacted quickest to head past Simon Moore.
Brentford almost struck back when Berahino's cross from the left fell to McGinn, whose low header was palmed away by Rachibka.
A quick Bees' break resulted in Berahino's cross from the right being volleyed across the goal by McGinn at the back post, while at the other end Lisbie set up Spring, who blasted over the bar.
Sloppy defending just before the break allowed Orient to double their lead when Harlee Dean played the ball into the path of Smith, who fired past Moore.
Rosler shook things up at half time by introducing Harry Forrester and Antonio German, but neither made a meaningful contribution during an at time turgid second half.
As Brentford looked to get back into the game Donaldson set up Jonathan Douglas but his shot careered onto the stand roof behind the goal.
Donaldson then tried his luck from 25 yards, but his well struck shot was wide of the left hand post.
The next chance fell to Jake Bidwell, who cracked a low free kick wide of the post as Orient saw out the game to record their first home win of the year.
Brentford: Moore, Logan, Dean, Legge (sub Osborne 68), Bidwell; Douglas, Forshaw, Diagouraga, McGinn (sub Forrester h/t); Donaldson, Berahino (sub German h/t)
Subs (not used): Lee, Thompson
Attendance: 4173 (831 Bees)