In an afternoon for James Collins and Jussi Jaaskelainen to forget, the Welsh team took full advantage of a poor Hammers side to claim their second consecutive win of the season
First, Jussi Jaaskelainen allowed Angel Rangel's attempted drive across goal to slide underneath his body and into the net, before Michu was able to pounce on James Collins' weak backpass to slide in and score the Swans' second before half-time.
Danny Graham added a third just after the hour mark to round off a thoroughly convincing win for Swansea.
Michael Laudrup named the same starting XI who trounced QPR 5-0 last weekend, but forward Scott Sinclair was absent from the bench amid reported interest from Manchester City
In one of two changes from last time out, Sam Allardyce's new signing Matt Jarvis was given a starting berth following his move from Wolves on Friday, with Matt Taylor dropping to the bench. Elsewhere, James Tomkins replaced Ricardo Vaz Te to bolster the defence.
Swansea were jittery in the opening stages, seemingly finding it difficult to get into the rhythm of the game, and West Ham went close to taking the advantage when Jarvis nearly produced an immediate impact on his debut as his whipped delivery from the left flew mere inches over the head of Kevin Nolan with just 90 seconds on the clock.
The scare woke the hosts up and they were soon at their fluid best, causing Allardyce's charges havoc down the wings with Rangel particularly impressing with marauding forward runs.
And it was the right-back's adventurous nature that handed Swansea the lead after he delayed his retreat back to defence to allow Jonathan de Guzman to find him just inside the area. A quick dart forward was followed by a low drive by Rangel which West Ham goalkeeper Jaaskelainen really should have prevented from bouncing up and into the net.
And that howler was a sign of things to come for the Hammers as Collins, under minimal pressure, managed to fluff a backpass to his keeper and allow Swans striker Michu to nip in and coolly prod the ball under the advancing Jaaskelainen to nab his third goal in just two games.
West Ham were struggling to assert any sort of pressure on the Welsh outfit, with many aimless balls being pumped forward in the vague direction of lone frontman Carlton Cole.
Jarvis, however, continued to shine on his debut, as he combined well with the experienced Nolan to power a half-volley towards Michel Vorm's goal – only to see it blocked by Chico – before the new-boy almost turned provider once more as the winger's flick-on saw Cole's header cleared off the line by Neil Taylor.
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Tomkins was replaced by striker Vaz Te for the start of the second half as Allardyce reversed one of his pre-match changes to try and give his side more impetus.
Swansea were in cruise control after the break. They were two goals to the good and can pass the ball all day. And that is what they did.
Boasting over 70 per cent of possession on the hour mark, Graham – otherwise quiet in the game – was set free by Leon Britton after typically patient play from the midfielder and aided by typically dire defending from West Ham, only to bend his shot the wrong side of the post with just Jaaskelainen to beat.
But Graham did not have to wait too much longer for his goal when Collins was again exposed at the back by De Guzman's clever ball into the box towards Wayne Routledge. The winger turned quickly and dinked a smart cross towards the far post for the striker to sweep home.
The remainder of the game was played out with relative ease, despite West Ham's attempts in vain to spark a revival, with a special moment of note for Swansea youngster Ben Davies who was handed his senior debut by Laudrup with just over five minutes remaining.