Although they had suffered bigger beatings at the hands of Liverpool and Arsenal this season, it cannot get worse than a home drubbing at the hands of a decimated Hammers outfit.

Goals from Lee Bowyer (two), Matthew Etherington, Jonathan Spector and a beautiful free-kick from Nolberto Solano gave the rampant Hammers by far their biggest win of the season.

The visitors must be given credit for taking their chances well, but all except the last goal were easily preventable.

Despite making five changes, Derby were equally poor in attack, the return of Scotland striker Kenny Miller making little difference as their goal drought reached five matches.

Even a January spending spree looks unlikely to save them – it is this kind of game they simply cannot continue to lose if they are to avoid the drop.

Against a side with only one win in their previous six league games, and one with almost their entire first team out injured, they will rarely get a better chance to take all three points.

But the match cruelly exposed all of their weaknesses – a lack of penetration, a dearth of creativity and a habit of conceding terrible goals.

In fairness, they kicked off full of running and commitment, although their aggression was slightly misdirected when Gary Teale and skipper Matt Oakley unleashed tackles that had George McCartney and Bowyer writhing in agony.

Left-back McCartney required treatment for two minutes after Teale’s challenge and he was unable to continue 14 minutes in following an aggressive – but clean - tackle from Giles Barnes. John Pantsil was the replacement, immediately swapping flanks with Lucas Neill.

Luis Boa Morte went close to opening the scoring, bursting clear down the right side and leaving Marc Edworthy – making his first appearance of the season – on the deck in the area.

The Portuguese’s left-foot finish was blocked but only to Carlton Cole, whose follow up was saved by Stephen Bywater.

Pantsil’s first real contribution was to collect the game’s first booking for an extremely late challenge on Andy Griffin.

West Ham were looking increasingly threatening as the half wore on, their best move of the match almost releasing Cole but still resulting in a free-kick inches outside the box.

It looked too close for a direct strike but Solano did his best to prove otherwise with a delightful effort against the crossbar.

Bowyer then earned himself a suspension for a foolish lunge on Barnes, for which he was rightly booked.

With half-time approaching, the visitors finally took the lead they deserved.

Solano’s cross found Cole in the box and his nod down allowed the criminally unmarked Bowyer to sweep the ball through Stephen Bywater’s legs and into the net.

It almost got worse for the home side immediately after the restart, Darren Moore easily shrugged aside by Cole, whose scuffed cross saw Boa Morte shoot too close to the goalkeeper.

The resulting Solano corner was just as poorly defended, Matthew Upson allowed to smash a shot against the bar, narrowly missing out on his first goal for West Ham.

Having failed to muster a single shot at goal in the first half, Derby could have levelled when Miller’s header from Lewis’ cross sailed wide.

But, in a frantic start to the second period, it was game over within eight minutes, first when Etherington and Bowyer were allowed the freedom of the area to exchange passes before the former fired home.

The contest was summed up by West Ham’s third.

A corner was partially cleared but the ball eventually fell to Spector, whose strike looked to have been blocked by Eddie Lewis, only for his fellow American to fall over the ball and send it over the line.

It was Spector’s first goal in English football.

Having introduced Steve Howard and Robert Earnshaw and over-committed up front, Derby were then hit on the break, Solano feeding Cole out wide and his cross was met by Bowyer’s perfectly-timed run.

To their credit, only a handful of the home fans headed for the exit, but the rest were simply stunned into silence.

But the exodus was not long in coming after Solano bettered his earlier free-kick with goal five, a stunning strike across Bywater and into the top corner.

Derby huffed and puffed trying to pull one back but the Hammers remained a threat on the break and could have made it 6-0 when Cole blazed wide.

The miss was greeted with ironic cheers from the travelling faithful, who were in party mood for the remainder of the game.