Scotland coach Vern Cotter was happy just to get a win over World Cup giantkillers Japan and indicated it could have been more convincing than the 45-10 scoreline suggested.

The 53-year-old New Zealander, who has revived an underperforming Scottish team since taking over in May 2014, said sterling first half defence had been crucial in holding off the team who stunned South Africa last Saturday.

“I wouldn’t say it was convincing,” said Cotter after the Pool B victory which also delivered a crucial bonus point.

“We managed to score points in the second half but I thought I thought we traded blows in the first-half.

“But in the second-half we managed to get over the try line and get a bonus point which we are every happy to do.

“The Japanese are deft passers of the ball and good at changing angles.

“The Japanese are a good side.”

The Scots ran through a tiring Japanese side who appeared to pay for their extraordinary efforts in beating two-time world champions South Africa. In the second-half, they scored five tries and 33 points to pull away from leading 12-7 at half-time.

Cotter, who said the Scottish had been focusing on Japan for 10 weeks, said it was good to get past the first match.

“We are very happy to get the win, get started,” he said.

“Watching the other sides play has been a bit nervewracking, especially the Japanese win over South Africa.

“However, Greig (Laidlaw the captain and man of the match) and the team kept their composure and come away with the win so we are happy.”

Laidlaw, who contributed 20 points with the boot on his home ground for his club Gloucester, said he could tell the Japanese were running out of gas.

“I did feel they were tiring in the second-half,” said the scrum-half. “I felt we had them at half-time.

“Credit to them, they held on at the end of the first-half but they were creaking.

“Vern said ‘don’t panic’ at half-time just hold on to the ball.

“I think this Scottish side is the fittest we have ever been. We believe we are in a good place fitness wise.”

Cotter, who was brought in after a successful stewardship at French giants Clermont, said he was delighted that Laidlaw had put up such a dynamic performance on his home turf.

“Greig is accurate in what he does and he punished them very clinically for their mistakes,” said Cotter.

The Scots go on to play the United States at the weekend and Cotter said he would rest some key players.

“We have a squad with 31 fit players and like I said at the outset every one of them should get some playtime,” said Cotter.