Cristiano Ronaldo scored twice as Portugal ensured a top-place finish in their Nations League group after beating Poland 5-1 in Porto.
Ronaldo converted a penalty after Rafael Leao had given Portugal a second-half lead and the 39-year-old added his second with an overhead kick in the closing stages.
Bruno Fernandes and Pedro Neto were also on target as the Portuguese led 5-0 before Dominik Marczuk struck Poland's late consolation.
While Portugal booked their quarter-final place, Poland's hopes were dashed and if they lose to Scotland on Monday, they will be relegated.
John McGinn's late strike clinched Scotland a 1-0 win against 10-man Croatia at Hampden Park to keep his side's hopes of retaining their Nations League A status alive.
Croatia were reduced to 10 men shortly before half-time when midfielder Petar Sucic received his second yellow card.
Spain ensured they will finish top of Group A4 by winning 2-1 in Denmark.
Luis de la Fuente's side, already assured of a quarter-final place, were cruising after Mikel Oyarzabal and Ayoze Perez scored in either half before Denmark pulled one back late on through substitute Gustav Isaksen.
Serbia kept their qualification hopes alive after Aleksa Terzic's late equaliser clinched them a 1-1 draw in Zurich against Switzerland, who were relegated despite Zeki Amdouni's second-half opener.
Northern Ireland took a big step towards towards promotion to League B as goals from Daniel Ballard and Dion Charles secured a 2-0 win against Belarus in Belfast. The North remain top of Group C3 after winning all three of their home games and play in Luxembourg on Monday.
Luxembourg finished bottom of the group after a 1-0 home defeat to Bulgaria, who are safe from relegation.
San Marino, who earned their first-ever competitive victory with a 1-0 win against Liechtenstein in September, remain in contention for promotion from Group D1 after Nicola Nanni's stoppage-time penalty rescued a 1-1 draw against Gibraltar.
In Group C2, Cyprus ensured a third-place finish after winning 2-1 in Larnaca against bottom nation Lithuania, who have lost all five of their matches.
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