Brentford boss Mark Warburton reckoned his boys became men at Brisbane Road on Saturday.
Striker Marcello Trotta struck on the stroke of half time to give the Bees a 1-0 win and send his side back in to League One's top two.
But Warburton's men were made to work hard to keep the division's leading scorers at bay when James Tarkowski saw red early in the second half for a second yellow card.
And the Griffin Park chief reckoned the hard graft would only stand his side - now only a point behind leaders Wolverhampton Wanderers - for the run in.
“Both teams realised there was a lot at stake. It was a big derby. The key for us was focusing on doing what we do well," said Warburton.
"After we went down to ten men, just look at George Saville at 20-years-old, Adam Forshaw at 21, Harlee Dean at 21. They made Alan Judge look like an old man at 24/25-years-old.
"But also look at the senior pros like Jonathan Douglas, Tony Craig, Clayton Donaldson, it was outstanding performances all round.
"I think we've learned from last year and are hopefully in good shape to move forward."
Bees keeper David Button has kept four successive clean sheets since a 3-0 defeat to Wolves at Griffin Park, as Brentford have collected 10 points from a possible 12 in their past four matches.
And Warburton was impressed with how his men reacted to a big game atmosphere in easy London.
"I can sit there and say to the players that it's just three points, but they're not stupid," he added.
"It was a sell out crowd, in front of the TV cameras, second versus third, east versus west and I thought the boys performed very well."