The 27-year-old's first international goal was enough to keep Scottish hopes alive of securing a playoff place for next year's finals.
Craig Levein's side now need to equal or better the Czech Republic's result against Lithuania when they take on world champions Spain on Tuesday.
"Three points was the main aim," said the Brighton forward.
"It was a great performance from the boys. Hopefully we'll have a similar performance against Spain.
"It's going to be harder on Tuesday against world-class opposition but we'll do the best we can."
Scotland lost the reverse fixture against the World Cup winners a year ago when they went down 3-2 at Hampden Park.