KEMAR Roofe and Liam O’Neil’s first-half strikes saw Albion complete the double over Arsenal to move up to third in Barclays Under-21 Premier League National Group One.
The Baggies dominated the first half and took the lead in the 18th minute when Roofe pounced on James Shea’s spill from Bradley Garmston’s cross.
Liam O’Neil headed in from a half-cleared corner on 38 to put David Oldfield’s side two up at the break.
The Gunners came out strongly in the second half and pulled a goal back thanks to Kris Olsson’s 63rd-minute free-kick from 25 yards.
But the visitors held out to secure another three points against the North Londoners, following last month’s 1-0 Hawthorns victory.
Oldfield said: "We passed it well in the first half and scored two good goals.
"We were less fluid in the second half, had less possession, and had to dig deep and defend.
"In recent weeks we've played well and at times not got the results we've deserved.
"Overall, today, the boys worked hard and got a very good result."
The Baggies were also buoyed by Craig Dawson captaining the side and getting 90 minutes under his belt on his return from an eye injury.
ALBION: Lewis, O’Sullivan, Dawson, C Jones, Garmston, O’Neil, Birch, Roofe (Pace 82), El Ghanassy (I Brown 72), A Nabi, Sawyers. Subs not used: Palmer (gk), Wedderburn, Smart.