Yokohama - Scotland must get "much, much better" very quickly or they will miss out on the World Cup quarter-finals, dejected coach Gregor Townsend warned Sunday after they were soundly beaten by Ireland.

Ireland romped home 27-3, scoring the only four tries in the match for a bonus-point win to be level with Japan at the top of Pool A after their opening games.

Townsend was at a loss to explain why his side lacked the "energy, accuracy and aggression" required at World Cup level.

"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 just missed the start of that game which was very disappointing," he said.

"We need to win our next three games. We have to bounce back and be a lot better against Samoa and carry that on to Russia and especially Japan who started the tournament well."

The coach said there was "disappointment obviously" at the Scotland effort.

"We have to play much, much better in our next three games if we are going to make it out of our pool," he said.

"We feel the game we play can pressure the opposition when accurate. It's a game that involves running the ball, kicking and defence and all those aspects have to be much better if we are to progress into the quarter-finals."

Townsend was left sweating on the availability of flanker Hamish Watson, who was stretchered from the field with a knee injury.

He was to undergo scans overnight which would determine whether he would take further part in the tournament