Leinster's Jamie Heaslip said it how he saw it: "I think we got beaten up around the set-pieces.
"As a pack, we lost out today," he said, following the 24-18 loss to Harlequins in Pool 2 of The Champions Cup at The Stoop yesterday.
Conor O'Shea's 'Quins moved three points clear of Leinster in second with Wasps just two further back after a bonus-point win in Castres.
"We talked inside. We've got a lot to do. The way it is after a loss like that, you just want to, you want to play tomorrow, almost," he said.
The club captain will have to wait until the return leg, in round four at the Aviva Stadium on Saturday evening to fully digest the bitter after-taste.
"We're really disappointed. We gave them some easy points in the first half to make it 9-9. There were some silly errors on our behalf, in terms of discipline."
It wasn't all doom and gloom. Leinster did come away with a losing bonus-point which could prove pivotal when the final points are totted up.
"We did a lot of good, I thought," said Heaslip.
"We launched well at times and carried well when we got into our shape.
"We've got a lot to work on and got a lot to do in the six-day turnaround," he concluded.