Clarets boss Sean Dyche admitted Spurs' late winner at Wembley was a bitter pill to swallow.
Burnley held out for 90 minutes, but substitute Christian Eriksen scored in the first minute of injury time, to snatch the points.
Dyche had started with three centre backs for the first time as Burnley boss, and a rearguard action largely restricted Spurs, but the final whistle confirmed a seventh defeat in nine games, albeit with performances starting to return to what we know the side are capable of.
Dyche said: "Yeah, I mean, inevitably it is (tough to take) because the players, overall, probably deserved something from the game.
"You can never guarantee it, quite obviously, after what happened, but I think the players are disappointed more in the fact, finally, you get done by what is just a lump down the pitch, and we've dealt with that well today.
"I was pleased with that aspect, they are a really good side, a direct side, but with a passing style.
"But they ended up playing long a lot today, and I think that's real credit to our players, because we kept the lines tight, they couldn't find a passing move that would open that up too many times.
"That's the only frustration, it ends up being a simplistic situation, which we've dealt with all day. The three centre halves were excellent, but two just get a challenge together, and it drops and they get a goal out of nothing really.
"But, on the other side, we've come down with a tactical platform, we've worked hard on it this week.
"The players have been open-minded and they've delivered that, so that's pleasing for a manager's point of view, although you go away with nothing in the end."
Asked about the shift to a back three - which Dyche played in at Chesterfield, he explained the decision: "It's something I played in myself, I think the timing of when, why, and the wherefores, we've had an up and down time and it's been growing lately, but the reason I changed it is I think the mentality is back, and it's been very solid.
"When we're mentally right as a group, they're very open-minded to take on whatever.
"Tactical changes can be yards, three, five yards here and there, different lines, and the players are very receptive to that.
"Early season I think there was a lot of confusion around it from off the pitch, on it, all the stories...lately we've got back to being what we can be, and I thought this was appropriate, and they would be open-minded to the work, which they have been all week.
"But they were particularly open-minded to deliver it. It's okay delivering it in training, it's when the whistle blows for real, and I think there was a good delivery of the tactical side, and the energy was outstanding."