Cristiano Ronaldo reached 99 international goals as he helped defending champions Portugal qualify for the Euro 2020 finals next summer.
Portugal will be able to defend the title they won in France in 2016 after a 2-0 win over Luxembourg saw them beat Serbia to the second automatic spot from their qualifying group.
It was a tough game for Portugal against stubborn and well-drilled opposition on a difficult pitch, but they got ahead with a superb touch and finish from Brune Fernandes six minutes before half time.
Luxembourg continued to frustrate the visitor, who only made sure of their qualification four minutes from the end thanks to an expert piece of goal-poaching from the Juventus man.
Goal line technology might have thought otherwise had it been active in the game, as Ronaldo prodded home Diogo Jota's effort right on the shadow of the line.
That took Ronaldo to 99 international goals, but despite having a few other opportunities he could not reach three figures for his country - and the wait for that landmark stretches on a further game.
Serbia were battling with Portugal for the second automatic spot, but they were held to a 2-2 draw against group winners Ukraine, who had already sealed qualification.
A 93rd-minute winner from Artem Biesiedin condemned Serbia to the play-offs as it stands.