Burnley boss Sean Dyche took aim at referee Craig Pawson after a controversial Laurent Koscielny winner handed Arsenal a 1-0 victory on Sunday.
Koscielny bundled the ball home in stoppage time at Turf Moor, but appeared to do so with his arm.
It marred an impressive performance from Burnley that restricted Arsenal to scarce sights of goal, Alexis Sanchez wasting great chances in either half.
Dyche was pleased with his side's display and bemoaned the referee's decision to allow the corner that led to Koscielny's questionable strike.
"You have to question the added time, the corner and whether it should have come in, the handball and question whether we should have dealt with it," he told Sky Sports.
"It's a poor way to end a game. We are disappointed in that but encouraged by the performance.
"We were taking on one of the super power clubs. Obviously it's the ultimate frustration with the last 10 seconds or so.
"The mood in the dressing room is not low, we know what the challenge is. It's more one of frustration because they have done enough to earn a point after keeping a good side quiet.
"There's a lot of positives to come out of this."
Defender Michael Keane added: "It is extremely disappointing, the lads put in a great shift, they were brilliant to a man. I have not seen [the goal] back but I heard it was handball and offside.
"You just hope these things come back to you across the season.
"It was one of those days. We come away without a point, but there are plenty of positives. We came in and took the game by the scruff of the neck and played some good stuff."