Russell Martin admits it was frustrating to be on the receiving end of Gibraltar's first competitive goal but the nervy experience did not shake his belief that Scotland are heading for the European Championship finals.

Martin was the lone centre-back in Gordon Strachan's ambitious formation at Hampden and he only had two attacking full-backs, Alan Hutton and Andrew Robertson, for protection.

The three-man defence appeared vulnerable in the early stages and the unthinkable happened in the 19th minute when Martin found himself out of position and Gibraltar exploited the space to give Lee Casciaro the chance to strike a historic equaliser.

But Scotland had hit four goals before Gordon Greer joined Martin in central defence after half-time and went on to complete a 6-1 victory.

The result leaves them level on 10 points with Germany and one behind Group D leaders Poland ahead of their next qualifier against the Republic of Ireland on June 13.

When asked what was going through his head when Gibraltar levelled, Martin said: "It was more of a frustration than anything. But fair play to them, they set up well.

"A team is always going to get a chance against you when you set up like that.

"Germany played the same way and they had a couple of chances against them and they are the world champions. So it shows you what can happen.

"But obviously we were disappointed to concede, especially so quickly after scoring. As a defender you want clean sheets and it didn't happen, but the way the lads bounced back and the goals we scored, it was great. We won the game. Job done.

"We were disappointed with the way we started the game but we got to grips with it after that. Everyone is happy to get three points and move on to the next one."

The Norwich defender claims he was comfortable in his one-man central defence - but they were given a surprise by Gibraltar's approach.

"It was fine," he said. "We spoke about it and worked on it all week. It was something we were comfortable with.

"We expected them just to play one up top but the first 10 minutes they pressed three really high. We didn't cope well enough with it.

"But I think after the first 10 minutes or so the system worked quite well in terms of chasing goals. We got four so that enabled us to go back to our normal system and dominate the ball a bit more because we weren't chasing goals."

Scotland sit behind Germany at the halfway stage of the group but they are the best third-placed team in the European qualifiers, a mantle that provides automatic qualification at the finish.

Martin said: "It's been a good one, 10 out of 15 and some really good performances. I think we are unfortunate not to have a few more points, the way we played in Germany and Poland as well.

"If we can carry that on for the second half of the campaign, I think we will do it."