Cameron Peupion grabbed a brace as Arsenal were put to the sword by Albionâs under-18s on Saturday.
Albion took time to grow into the contest, but once Levi Laing put one past his own goalkeeper after 25 minutes, the visitors didnât look back.
Australian Peupion, who joined the club in August, fired into the bottom right corner from the penalty spot to double Albionâs lead, before Todd Miller added a third just before the break.
Andy Moran got Albionâs fourth on the hour mark, before turning provider late on as Peupion netted his second of the afternoon in the last minute.
The result moves Albion up to sixth in the Premier League South table.
âProfessional development phase coach James Baxter said, âResults-wise we havenât quite found a consistency, but our performances have been really good.
âWeâve been on top in a majority of our games. We just havenât had that clinical edge, but that came together on Saturday. We have won two, drawn two and lost one so itâs not been a bad start.
âWeâre averaging 15 chances a game at the moment and kept a clean sheet on Saturday so it was a dream game for [Head Coach] Mark Beard and myself.
âTheir attitude and the way the players conduct themselves has been phenomenal whether we win or lose. They are such a hard working group and the result against Arsenal saw the fruits of their labour.â