Crystal Palace boss Alan Pardew complained about decisions that led to both Arsenal goals but said he was pleased with his team's effort despite Saturday's 2-1 defeat.
After Palace's would-be equaliser at the death crashed against the base of the post, Pardew was left berating referee Mark Clattenberg.
The Eagles manager felt Pape Souare's first-half foul on Danny Welbeck that led to Santi Cazorla's penalty occurred outside of the box, and then said Arsenal's second goal should have been ruled out for offside in the build-up to Olivier Giroud's strike.
"The first goal was a mistake by Pape -- he should do better, although it was tough on us because it looked like the incident was outside the box," he said.
"The second goal was offside. That call should have been made. A minute before half-time you've got to get that call right."
Even though the late fight back fell short, Pardew hailed the performance of his side as the best he has seen since taking over at Selhurst Park at the turn of the year.
"We took a tactical decision to take the game to Arsenal," he added. "We continued with the game-plan and I was very pleased with the reaction. Its probably the best we've played since I've been manager.
"The chance when it hit that post and it fell in to the goalkeeper's hands summed our day up. I thought it was going to spin into the net.
"There was some great team play and probably the best players were on our team. But we've lost and sometimes that happens. Our final moment in that box needs to improve but we are not far away from being a decent team."