The Gunners were 4-0 down just before half-time but fought back to level the score and force the fourth-round clash into extra-time, before sealing a dramatic victory late on.
“You always see new things in our game and that’s why it’s never boring,” Wenger told Sky Sports. “It was 4-0 and it could have been one or two more but in the second half we created chance after chance.
“You cannot play for Arsenal and give up, no matter what the score is.
“The players understood that at half-time and that you cannot go out in the second half with the same performance. Give them credit, they responded very well and showed that.”
Reading came storming out of the blocks and raced into a 3-0 lead inside 20 minutes thanks to strikes from Jason Roberts and Mikele Leigertwood either side of Laurent Koscielny’s own goal.
And Brian McDermott’s side extended their advantage when Noel Hunt headed home, before Theo Walcott pulled one back for the visitors on the stroke of half-time.
Substitute Olivier Giroud’s header then made it 4-2 in the 64th minute, before Koscielny made amends for his earlier own goal with a close-range finish one minute from time to give the Gunners late hope of a dramatic comeback.
Reading looked like they would hold on for the win despite being pegged back to 4-3, but Carl Jenkinson drilled home in the 95th minute to force the tie into extra-time, despite Walcott’s original effort appearing to have crossed the line before falling to the defender.
Marouane Chamakh then put Arsenal ahead for the first time with a low strike from the edge of the box.
But Reading refused to give in and equalised when Pavel Pogrebnyak’s header beat Damian Martinez in the Arsenal goal in the 116th minute.
Yet it was the Gunners who had the final say, with Walcott putting Wenger’s men ahead again and Chamakh grabbing his second of the night with a neat chip to cap an extraordinary night at the Madejski Stadium and book the Londoners’ place in the fifth round.
“It was an unbelievable game,” said man-of-the-match Walcott. “We started very sloppily and we had to wake up.
“The boss told us that we had to go at it and that it wasn’t good enough, and we showed everyone what we can do. We never gave up.”
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