Scotland coach Vern Cotter says he was pleased with his side's performance in the opening 45-10 whipping of Japan but still rang the changes for Sunday's second Pool B match against the United States.

The 53-year-old New Zealander -- who has revived the morale of the team since he took over in May last year -- had said in the immediate aftermath of Wednesday's ultimately impressive win against a tiring Japanese outfit that he would deploy fresh faces given the short turnaround in between games.

Scotland -- who did not let themselves get out-thought or out-fought by the Japanese as the South Africans had last weekend -- will be looking to add a second bonus point win to their tally against the team seen as the weakest in the group and who began with a 25-16 loss to Samoa last Sunday.

The Scots lead the pool by a point from Japan and Samoa with the Springboks, who face the Samoans on Saturday, on two points -- the Japanese have played a game more than the others.

"We said from the start that we'd need the whole group of 31 players for this campaign," said Cotter.

"We've known this schedule for a long time and have tried to keep continuity in selection, while also introducing fresh legs to what will be another very physical challenge this Sunday."

On that note Cotter promoted all the players who filled the replacements bench into the starting line-up with notably scrum-half Henry Pyrgos replacing Greig Laidlaw -- man of the match against the Japanese for his 20-point contribution -- both as scrum-half and captain.

Pyrgos, who captained the Scots in the warm-up Test against Ireland, will have Finn Russell, who scored one of Scotland's five tries against the Japanese on what was his 23rd birthday, as his halfback partner.

Centre Mark Bennett gets another start and will be looking to add to his two-try haul from the Japan game.

Cotter also called up two fresh wings in Netherlands-born Tim Visser and Kiwi Sean Maitland allowing veteran Sean Lamont and Tommy Seymour to rest up after good performances against the Japanese.

In terms of experience in a side that has plenty of new talent, Cotter will rely on lock Richie Gray and flanker Alasdair Strokosch, who will win their 48th and 47th caps respectively.

"I was pleased with both the commitment and composure against Japan, particularly towards the end of the game, however we are always working and looking for things on which to improve," said Cotter.

Team (15-1):

Stuart Hogg; Sean Maitland, Mark Bennett, Peter Horne, Tim Visser; Finn Russell, Henry Pyrgos (capt); Josh Strauss, John Hardie, Alasdair Strokosch; Grant Gilchrist, Richie Gray; Jon Welsh, Fraser Brown, Ryan Grant

Replacements: Ross Ford, Alasdair Dickinson, Willem Nel, Tim Swinson, Ryan Wilson, Greig Laidlaw, Duncan Weir, Matt Scott

Coach: Vern Cotter (NZL)
Source: AFP