A late try rescued a bonus point but could not prevent Welwyn from slipping to defeat away to Hackney.
They went down 15-14 in the Counties One Herts Middlesex clash on the Marshes, although the losing point did help them move up one place in the standings to eighth.
From the kick off the home side looked intent to play attacking rugby and put Welwyn under pressure.
A line out five meters from the line was dealt with but a second on 12 minutes proved more fruitful for Hackney as they secured the ball and drove over.
The conversion gave them a 7-0 lead but Welwyn did respond.
A charge down from Christian Salisbury had put Hackney under pressure and good link-up play by forwards and backs gave Harry Slade the chance to break, a run that was stopped illegally 10 meters from the try line.
Welwyn opted for the scrum and following a number of pick and go’s, Thomas Emery scored just to the left to the posts, the conversion bringing parity once again.
The next score could have gone either way but it was Hackney who got it as Welwyn ran out of defenders, and there was a further blow as an injured shoulder spelt the end of outside centre Maciu Selanabuka's game.
Slade moved from number eight into the backs with the experienced Rob Picken coming on in the forwards.
Welwyn did finish the half with a period of sustained attacking pressure but the interval ruined that and the first 20 minutes of the second period belonged to Hackney.
They pinned Welwyn and it needed some excellent tackles to prevent a third home try, most noticeably from Ryan Saunders.
In the end Hackney only had a penalty to show for their efforts, although it did move them eight points clear.
With two scores needed, Welwyn took the attack to the home side.
A frantic high tackle gave the visitors a man advantage too but a shot at the posts drifted wide.
A deliberate knock on by the Hackney scrum-half was also deemed to be a yellow card offence and it finally brought a gap, the ball spread wide to Slade who stepped inside his opposing number to score on the last play of the game.
A weekend off will allow tired bodies to rest before a difficult home game against second-placed Brunel University on November 9.
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