Second half strikes from James McAtee, Liam Delap and Alpha Diounkou were enough to help the hosts overcome the ten-man Gunners at the Academy Stadium and seal a third consecutive PL2 win in the process.
The visitors took an early lead when Nikolaj Moller's sixth minute effort squeezed agonisingly over the line after Taylor Harwood-Bellis had blocked Flo Balogun's initial effort on goal.
Enzo Maresca’s men immediately began searching for a way back into the game, and they almost found it within a minute when Nmecha beat goalkeeper Karl Hein to a beautifully threaded through ball, before being brought down.
The visiting stopper was given his marching orders for the challenge, with the Gunners forced into putting outfield player Taylor Foran between the sticks for the remaining 83 minutes.
The breakthrough arrived as Nmecha raced on to a clever reverse pass from Rogers down the left of the box before calmly slotting home a 24th minute equaliser into the far corner.
The crucial second came courtesy of super-sub McAtee just before the hour, the midfielder picking up play just outside the box before calmly placing a low effort through a crowd of bodies and inside the near post.
The game was finally put to bed when Delap got the goal his performance fully deserved, finding a pocket of space just inside the box before smashing the ball into the top corner to give us a two-goal cushion.
Substitue Alpha Diounkou then added further gloss to the scoreline when he slid home at the back post to put away Bernabe's low cross.
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