Scotland did not start with enough "energy, accuracy and aggression" in their Rugby World Cup loss to Ireland, conceded head coach Gregor Townsend.
The Scots began their Pool A campaign with a 27-3 thumping at the hands of Joe Schmidt's men in Yokohama.
Clinical Ireland scored three of their four tries in their opening 25 minutes, pouncing on Scottish slackness.
"Ireland are probably the best team in world rugby if you give them a 15-20-point start," said Townsend.
"We didn't start with the energy, accuracy and aggression that is required to beat a team like Ireland."
When asked why, in a match of such magnitude, his players lacked those qualities, Townsend replied: "That's what we're asking each other. The energy wasn't as high as it has to be to beat a team like Ireland.
"We didn't show our best version of ourselves. I've seen that in training and in the last two or three games, but when you don't do that against the best teams in the world, they will punish you.
"The World Cup has just begun and we have to play much, much better in our next three games if we're going to make it out of this pool.
"But I believe in this squad and that they will bounce back and be much better against Samoa in eight days' time."
Watson to have scan on knee injury
Scotland face the Pacific Islanders in their second outing next Monday, before tackling unfancied Russia and host nation Japan.
They may be forced to do so without flanker Hamish Watson, who was carried from the field after damaging a knee at a ruck.
However, fellow open-side Jamie Ritchie has recovered from a facial injury and back-row Magnus Bradbury, not selected in Townsend's 31-man tournament squad, remains in Japan as cover.
"We will hopefully be getting more information [on Watson] tonight if he can get a scan," Townsend said. "It doesn't look good when a player is stretchered off the field so we'll wait and see later tonight.
"The good news is Jamie Ritchie will be available for our next game. So if Hamish does miss that game, he can play open-side, and Fraser Brown who came on and played open-side today did a good job.
"Magnus is still in Japan, we held on to him just in case we didn't have any luck with injuries this weekend. So if Hamish was to miss out, then Magnus would be the obvious replacement."
'Minimum standard is effort and fight' - analysis
Former Scotland captain Rory Lawson on BBC Radio Scotland
The minimum standard that Scotland fans ask for is effort and fight. There was no tooth or bite to that performance. Normally you have something to hang on to - attack play or defensive solidity - but there was nothing.
In energy and mindset, Scotland were not at the races. Scotland were bullied physically up front. The Irish pack believe, man-for-man, they are 10-15% better than Scotland. They looked 25% more physical and in control than Scotland today.
Former Scotland prop Ryan Grant
Scotland's attitude didn't look right. It's so disappointing to watch - especially in a World Cup opener where they should be right up for it.