"Devastated" – one word summed up the mood in the Leinster camp after they managed to dominate possession and territory, yet failed to secure at least a draw from the latest compelling episode of European rugby's fiercest rivalry at the Stade Marcel Michelin.
As Clermont coach Vern Cotter continued to bemoan Nigel Owens' refusal to allow a late line-out, with the home side seeking to deny their familiar foes a losing bonus point by scoring a try, Leinster were simply distraught to have expended so much blood and sweat in defeat.
"You can't put that much energy and effort into the game and create the opportunities that we did only to come away disappointed," said Schmidt, whose side will at least have a swift opportunity for vengeance in next Saturday's return clash at Lansdowne Road.
"It is incredibly disappointing. It's going to be tough to try and forge ahead for next week. We need to get ourselves up.
"We've a fair few bruised bodies in there. It was fairly combative stuff at times, not always on the ball. It's what you expect. It's pretty tough going."
Schmidt's side sought the win and he fully empathised with Jonny Sexton's decision to refuse the kick at goal from a mud bath, one that may have earned his side a draw at the finish, instead deciding to cross-kick for Fergus McFadden early in the second half.
Ultimately, a raft of silly, uncharacteristic lapses pockmarked a marvellous defensive and physical effort, with a late line-out implosion undermining Leinster's attempts to course a clearly anxious home side.
"A couple of line-outs went astray, one maybe seven or eight metres from their line and another one just on their '22'.
"Those two are lingering in my head at the moment. That's just disappointing, but they had one on our '22' where they didn't quite get it right, either.
"The guys put in a pretty gutsy display and challenged them at times, maybe gave away a couple of penalties quite cheaply and let them off when we had them under pressure on a couple of occasions.
"In the second half, there were a lot of missed opportunities for both teams. When it came to the crunch, both teams didn't quite deliver at set-piece time on a few occasions.
"There was a lot of pressure out there, it was a very close game and it got quite cagey.
"It was a bit mixed, it was almost like both teams stopped playing a little bit. It was there for the team that wanted to go after it and it was almost like both teams were a bit cagey.
"Listen, we've got to put it behind us and move on. A six-day turnaround is short and we've just got to make sure we're in the best shape possible come next Saturday."
Clermont coach Cotter is hoping that his side can build upon this success and ensure that they do not subside in Dublin as they did at this stage of the competition two seasons ago.
"We'll probably turn the page on this," said Schmidt's old boss. "We'll have a quick look at what we did and try to do things better.
"We've got six days to try and do better than we did tonight, if we want to be able to contest. We weren't able to contest there two years ago. We'd like to be able to contest better than that."