Will Bell kicked a penalty for Horsham as the Green and Whites applied early pressure and took the lead after two minutes.
Opportunities thereafter went begging from a combination of wrong options and poor execution, and when coupled with some weak tackling, Hammersmith & Fulham took control to run in five tries and secure a comfortable win.
Head coach Nick Stocker revealed he was missing four or five regulars and their young replacements are certainly good enough to compete at this level.
He said: “We were a young team and the youngsters we brought in were 19 and 20, while the average age of our players is around 22.
We had a new number 10, 12 and 13 partnership and it takes time to gel.
They are certainly quite capable of playing at that level but on Saturday they weren’t able to perform.”
It was certainly going to be a tall order filling the shoes of players such as the skipper Tom Johnson and centre Johnny Ordidge.
Stocker said: “One of the challenges we have as a club is the step up from junior level to senior.”
Horsham are expecting to bounce back from their defeat this Saturday when they visit bottom of the table Crowborough in London 2 South East.
Stocker’s side are sixth in the table and expect to have at least a couple of players back and available to play.
He said: “It’s an all Sussex derby and we are hoping for a result.
We should have a better side out – that’s not to say the youngsters who played aren’t good enough – they are – they just need to step-up to senior level rugby.”
Horsham currently lie sixth in the table and are pleased with the start they have made to their campaign with 11 points and two wins coming from their first five games.
Their league match at Crowborough on Saturday kicks-off at 3pm.
Match report by Graham Carter - WSCT