Simon Grayson thought Preston North End's first-half performance against Arsenal was as good as anything in his time in charge at Deepdale.
PNE led from the seventh minute of the FA Cup clash through a Callum Robinson goal, only to be pegged back by a Gunners equaliser 50 seconds after half-time from Aaron Ramsey.
A deflected shot from Olivier Giroud in the 89th minute sent Arsene Wenger's men through to the fourth round.
North End manager Grayson said: "It was difficult to speak to the players after the game and know what to say because of how well they had played.
"They can be extremely proud of their performance, we made a very strong team look very ordinary in the first half.
"On the other side of it, we wanted to win the game or at least draw it, so we are disappointed to have conceded so late - it wasn't what we deserved.
"No one would have begrudged us had we won the game or drawn it.
"The performance in the first half was as good as I've had from my team since I've been here."
Grayson admitted missed chances in the opening 45 minutes were to ultimately prove costly.
They had chances to stretch the lead, with Robinson getting the ball in the net a second time, only for it be ruled out for a push on Gunners keeper David Ospina by Paul Huntington.
"You have to take your chances," said Grayson.
"If the ball across from Callum Robinson in the first half had been a bit slower, it might have got to Jordan Hugill.
"I didn't think Callum's header should have been disallowed.
"In terms of the plans we wanted them to carry out as a team, the things we worked on, they did it to a man.
"We dropped when we needed to, pressed when we needed to and when we had the ball we passed it well and broke quickly.
"We had some really good chances but unfortunately didn't get a second goal when we were really on top, that would have been a key element of the game.
"At half-time, we told the players to start brightly because there would have been a word or two said in their dressing room.
"But when you give a player like Aaron Ramsey time - it wasn't a great deal of time - he put it in the back of the net.
"That rocked us but we still stayed in the game and asked questions of them.
"Then we got done by a deflection which was a cruel way to lose the game."