The Scots steered their campaign to qualify for South Africa back on track with a much-needed win over Iceland at Hampden in April, which has lifted them to second in Group 9 with three games remaining.

Hartley is now well aware of how important it is to maintain a winning streak at this stage of the competition as they prepare to travel to Oslo for the crunch clash on August 12.

"It's important that we win the game to give ourselves a chance," he said.

"Any away game is going to be tough but we've got to go there and be positive and try and believe that we can win it.

"We had a good result against Iceland so we have to be positive and see where it takes us.

"Everybody wants to get to a World Cup and hopefully we can get the right result in Norway."

Hartley is expected to sign for Bristol City on Monday after a successful two-and-half years at Celtic.

But the 32-year-old admits representing Scotland at the World Cup finals would be the pinnacle of his career.

He told BBC Scotland: "Being an international player, that's what you try to achieve, major finals.

"It doesn't come much bigger than the World Cup finals so we would love to get there.

"Only time will tell but if we did get there it would be a fantastic achievement."