Cristiano Ronaldo stormed off the pitch before fulltime when he was denied a clear stoppage-time winner in a 2-2 draw in Serbia, while Belgium were held 1-1 by the Czech Republic in World Cup qualifiers on Saturday.
Ronaldo threw off the captain's armband and headed for the tunnel when his effort was cleared by Serbia defender Stefan Mitrovic after it had crossed the line, with Dutch referee Danny Makkelie waving play on.
With no VAR in place to review the decision, Serbia held out for a draw having fought their way back into the match from two goals down in Belgrade.
The hosts looked to be down and out after Diogo Jota scored twice in the first half for Portugal, but Aleksandar Mitrovic reduced the deficit early in the second half to become his country's top scorer with 39 goals in 63 appearances.
Filip Kostic made it 2-2 on the hour and the game ended in chaos as Nikola Milenkovic was shown a straight red card for a violent challenge.
The Serbs and Portugal both have four points in Group A, with Luxembourg third on three points after their shock 1-0 over Ireland in Dublin.
Gerson Rodrigues's superb goal secured the upset victory that left the Irish bottom of the five-team group behind Azerbaijan.
In Group E, Romelu Lukaku cancelled out Lukas Provod's opener to give Belgium a 1-1 draw away to group leaders Czech Republic. Belarus beat Estonia 4-2 to move into third place behind the Belgians.
Elsewhere teams continued to shine a light on human rights issues in Qatar.
Norwegian and Dutch players wore t-shirts highlighting their desire for change in Qatar, with Denmark saying they will join in the protests when they host Moldova on Sunday.
Norway's protests did little to help their fortunes on the field as they were on the wrong end of a 3-0 drubbing at the hands of Group G leaders Turkey.
Ozan Tufan scored twice for Turkey and Caglar Soyuncu added a header to outclass the Norwegians.
Netherlands bounced back from their defeat to the Turks in their opening qualifier by beating Latvia 2-0, with Steven Berghuis and Luuk De Jong getting the goals.
Montenegro beat Gibraltar 4-1 to go second in the group ahead of the Dutch and Norway.
Russia rose to the top of Group H thanks to two first-half goals from Artem Dzyuba in a 2-1 win over second-placed Slovenia while Croatia's Luka Modric won his 135th cap as his side edged a 1-0 win over Cyprus.
Slovakia fought back from two goals down to draw 2-2 with Malta, putting them in fourth place behind the Croats.