Gallagher was naturally disappointed after Wednesday's 1-0 defeat by Israel in Netanya but will remain positive as he looks ahead to the start of their World Cup qualifying campaign ahead of the European finals.

"It's obviously difficult losing any game of football," said the Motherwell centre-back, who had won all six of his previous internationals .

"It's disappointing but we have to keep positive.

"It has obviously been a historic week for the nation reaching our first major tournament for 22 years. So we have to keep positive and get our sights set on December and the draw for the World Cup, and look forward to that.

"I know it will feel like a sour note but we have to stay positive. We have to take that confidence from reaching a major finals and take it into the draw in December for the World Cup and be fully focused on that in March.

"We will put the Euros on the back burner until we compete in the World Cup. We have to get our heads focused on that before we can think about the Euros."

Scotland started their toughest international schedule to date with 120 tough minutes in Serbia followed by the emotion of the penalty shoot-out and the achievement of ending a long wait to return to the international stage.

Some well-publicised celebrations followed ahead of trips to Slovakia and Israel but Gallagher does not believe the exertions of the first game were to blame for their subsequent narrow defeats.

"The boys are professional, we knew we had a job to do," the 29-year-old said. "At the end of the day, it is hard to come away from home. We were on the road for 10 days and it has obviously been difficult.

"Israel are a good team, it was a close game, and obviously Slovakia are a good team.

"But I think in those two games you could see we are more positive, we are trying to get at teams away from home, where Scotland would maybe sit in.

"All the games between us and Israel have been tight games and the first goal always matters, but we had a lot of chances in the game and I think we could have come away with a victory.

"There were a few penalty claims as well, the boys saw a few handballs. But we didn't get that rub of the green we needed.

"You could see with the number of chances we are creating and the way we are playing and pressing, it shows the positive step that the boys are making. Hopefully we can continue to do that but obviously get results in the end as well."