David Healy, the competition's top scorer, notched two goals to help Northern Ireland go second in Group F with a 3-1 victory over Liechtenstein.
Three of the night's six qualifiers involved teams in Group A where Portugal and Serbia's dropped points enabled Finland to move above them in the table with a 2-1 win at home to Kazakhstan.
Portugal found themselves a goal down in the 10th minute when Armenia's Robert Arzumanyan headed in a corner.
Manchester United winger Ronaldo calmed the visitors' rattled nerves in the 38th when he robbed an opponent and weaved and jinked his way into the penalty area before sliding the ball into the net.
Serbia suffered a worse fate in Belgium where two goals from Moussa Dembele and another from Kevin Mirallas gave the hosts a 3-2 victory.
Finland went second in the group when goals from Alexei Eremenko Jr and Teemu Tainio got the better of Kazakhstan, who replied through Dmitriy Byakov.
Poland lead the table with 19 points from nine games,
Portugal have 15 from eight and Serbia have 14 from the same number of games. Belgium are fifth with 10.
TOP SCORER
Northern Ireland jumped above Spain into second place in Group F with striker Healy taking his goal tally in the competition to 11, four more than anyone else.
The Fulham player headed home in the fifth minute before half an hour later intercepting a botched Liechtenstein free kick to hammer the ball past the keeper from 18 metres.
The third Irish goal came in the 56th minute from Kyle Lafferty. Confusion in the closing minutes allowed visiting Liechtenstein to pull a goal back through Mario Frick.
The win lifted the Irish within two points of leaders Sweden, who have 18 points from seven games. Spain are third with 15.
In a Group E battle of two sides looking for their first points, Indrek Zelinski's last-minute goal gave Estonia a 2-1 win over Andorra in a bad-tempered encounter in Tallinn.
A second-half goal from Yiannis Okkas gave Cyprus a 1-0 away win over Group D bottom side San Marino, who have yet to pick up any points.