Swansea leap-frogged Southend to take over leadership of League One thanks to a Lee Trundle-inspired performance.
Swansea goal-scorers Akinfenwa and Trundle celebrate
The striker ran the Shrimpers ragged at Roots Hall, first putting the Swans ahead with a rifled left-foot shot after Owain Tudur-Jones flicked on.
Then Trundle's shot from a tight angle was half-saved before Adebayo Akinfenwa slammed home the rebound.
Freddy Eastwood volleyed home late on from Kevin Maher's corner to give Southend hope, but Swansea held out.
Swansea are now top of the pile on goal difference from Huddersfield, who also moved above Southend after a 2-1 win away to Yeovil.
Southend: Griemink, Hunt, Edwards, Barrett, Wilson, Campbell-Ryce, Guttridge (Bentley 68), Maher, Cole (Lawson 79), Eastwood, Goater (Gray 68).
Subs Not Used: Prior, Smith.
Booked: Barrett, Campbell-Ryce, Wilson, Bentley.
Goals: Eastwood 81.
Swansea: Gueret, Tate, Monk, Iriekpen, Ricketts, Britton, Tudur-Jones, O'Leary, McLeod (Robinson 88), Akinfenwa, Trundle.
Subs Not Used: Austin, Forbes, Martinez, Connor.
Booked: Tate, Monk, Iriekpen.
Goals: Trundle 40, Akinfenwa 47.
Ref: D Deadman (Cambridgeshire).