Two moments of class from Leon Knight were enough to seal the points for Swansea as they ended Brentford's unbeaten start to the season.
Striker Leon Knight celebrated a brace of Swansea goals
The livewire striker pounced either side of the break to seal the points in an end-to-end thriller at Griffin Park.
First Knight drilled a low drive inside the far post from 18 yards, then cut inside to fire into the top corner.
The visitors could have been further ahead, with Adebayo Akinfenwa and Leon Britton both hitting the woodwork.
Brentford: Nelson, O'Connor, Tillen (Osborne 45), Heywood, Griffiths, Pinault, Brooker, Cox (Willock 85), Rhodes (Tomlin 53), Kuffour, Moore.
Subs Not Used: Masters, Carder-Andrews.
Booked: Heywood, Pinault, Osborne.
Swansea: Gueret, Amankwaah, Austin, Iriekpen, Lawrence, Tate, Britton, Pratley, Butler (Robinson 70), Akinfenwa (Fallon 70), Knight.
Subs Not Used: Williams, Way, Oakes.
Booked: Knight, Britton.
Goals: Knight 37, 55.
Ref: G Poll (Hertfordshire).