Swindon Robins' impressive form continued as they edged to within three points of league leaders Poole with a comfortable 53-37 win over Lakeside.
The Hammers themselves remain in third and had looked to close the on the top two, but Swindon were far too good at the Abbey Stadium.
Troy Batchelor enjoyed his best night of the season unbeaten by opponent with 13+2 and Hans Andersen gave him excellent support with 12+1.
But new signing Dawid Lampart was arguably the star of the show for Swindon as the Pole scored consistently from the reserve berth with 11+1.
Lakeside battled but none of their side could hit double figures with Davey Watt and Peter Karlsson top-scoring on 9.
Bees slip-up again
For the second successive night, Coventry Bees missed the chance to claim their first away win of the season after going down 46-44 to Birmingham Brummies.
Coventry missed the chance to win at King's Lynn on Wednesday as they let a lead slip, and they did the same at Perry Barr - where at one point they led by ten.
With flying reserve Adam Roynon - a late call-up for the meeting after his British semi-final at Sheffield was postponed - again enjoying a points bonanza with paid 15, Bees should have had the firepower to take a maximum four points from the meeting.
In the end they had to settle for just one after seeing a 32-22 lead turn into a 44-46 defeat with the often-criticised Birmingham top riders rescuing their side late-on.
Bees boss Blayne Scroggins said: "We've let it go again, but we've come here and four riders have scored nearly all of our points.
"I'm sorry for the fans and we're absolutely gutted - ten points up, and it just didn't happen again. The track slickened off but there are no excuses, Birmingham did well to come back and they never gave up.
"The performances are getting better but we're so far behind that we haven't got time. The play-offs are getting further away and we've just got to rally round and get heads up for Friday night."
Birmingham were led home by Polish ace Seb Ulamek on 13 with Danish GP star Bjarne Pedersen also hitting double figures.
Roynon again top scored with good support from Kenni Larsen whilst Chris Harris also hit 10.