JUDGING by their first game against Samoa, the United States lack the verve and unpredictability of the Japanese. Nonetheless, there is a belief within the Scotland camp that, if they are to beat the Americans tomorrow and make it two wins out of two in Pool B of the Rugby World Cup, they will have to improve on their own performance against the Japanese.

For one thing, there is the significant matter of the four-day turnaround. When you are low on energy levels - and more than a few members of the Scotland squad will be in that position some time before the end of the game at Elland Road - you make mistakes more readily. The Scots will thus have to play with greater consistency from the start than they did in their 45-10 win over Japan, to ensure that if and when the mistakes come, the Americans are in no position to capitalise.

Another reason is the belief that the US will not be as flat as they were against Samoa. They competed well up front, and finished strongly as they tried to claw back a 25-16 deficit, and with a little more accuracy with the boot could have ended the game with a bonus point for a narrow defeat. Having lost that match, they know they will almost certainly be out of the tournament if they are beaten by Scotland, so can be expected to redouble their efforts.

Then, more significantly in the wider scheme of the tournament, Scotland need to get better because there will be tougher challenges to come. In the Japan game we saw the team had learned the lessons of the warm-up matches. Tomorrow, they need to show they have cut out some of the shortcomings that were still evident in that match, above all a vulnerability in defence, both at the lineout and in midfield, where there were too many missed tackles.

“We’re going to have to step it up another notch,” Ryan Grant said yesterday after being named in Vern Cotter’s starting line-up. “We’re constantly about improving.

“We said from the Ireland game to now that we need to get better in the next game and nothing has changed. Against Japan, the boys brought out a good second-half performance, but there’s still stuff to improve on and we hope we can iron some of those creases out against the USA.

“Within the squad we've always believed in ourselves and knew we were capable of playing good rugby. In the past we were showing it in some set phases and then slipping up in the next ones. The key is doing it consistently.

“We’re constantly trying to improve every game and learn from our mistakes. We hope those mistakes will get less and less.

“There’s a potential pitfall in every game, but to get anywhere in this competition, consistency is the key. We can't play well two days ago and not turn up on Sunday against the USA. The key for us is to back that performance up. We don't want to be the team that’s a flash in the pan, a one-off. We want to back it up week in, week out.”

Grant as an individual also wants to back things up week after week, but faces a tough fight to win selection in the starting line-up for the forthcoming games against South Africa and Samoa. Alasdair Dickinson, his rival for the No 1 jersey, is in the form of his life, and he is also part of an all-Edinburgh front row along with Ross Ford and WP Nel that is now firmly established as the first-choice combination up front.

“As far as I’m concerned I’m going to go out and play the best I can and if that is enough, great,” Grant said when asked if Cotter, the head coach, had told him what he needed to do to win back a regular place in the team. “There has been no mention of what will happen next.”

What needs to happen against the US if Grant is to have a chance of holding on to the jersey is for Scotland to maintain the solidity in the scrum that they showed against Japan. “We go into every game trying to have the best set piece we possibly can, but the way the game is today, teams are strong, there’s not much of a hit in the scrum any more,” Grant added. “If we can get ascendancy there, we’ll definitely take that advantage.

“For ourselves it’s first thing first things first, clean ball. There’s no point in having a dominant scrum if you’re going to get pinged, and we’ve seen time and time again with scrums that sometimes they can be a lottery. So first things first – get the ball to the back of the scrum and unleash our backs.”

If Scotland do gain the upper hand in the scrum, it will be the Americans who begin to concede penalties. They gave away 15 against Samoa and paid the price. Provided Grant and his colleagues keep up their improvement, they should again win well.