Portugal scored six goals against Bosnia including a Cristiano Ronaldo double to grab a ticket to the Euro 2012 finals while Ireland, Czech Republic and Croatia completed the lineup without the need for a frenzied finale to their playoff wins on Tuesday.
Portugal's second leg was the only tie still finely balanced following a goalless draw in the first match and, after letting Bosnia back into the game twice, they finally ran out 6-2 winners after the visitors were reduced to 10 men.
It was a lot easier for the other three qualifiers, who had established comfortable first-leg cushions with Ireland beating Estonia 5-1 on aggregate and the Czechs and Croats overcoming Montenegro and Turkey by the same 3-0 aggregate scores respectively.
While celebrations were in full swing in Dublin before the Irish had even kicked off holding a 4-0 lead from the first leg, there was everything to play for in Lisbon.
Early goals by Ronaldo and Nani put the 2004 runners-up 2-0 ahead in the first half before Bosnia got a lifeline when Zvjezdan Misimovic converted a 41st-minute penalty.
The visitors' hopes were short-lived though as Ronaldo's second goal eight minutes after the break restored Portugal's two-goal advantage and a minute later Bosnia were reduced to 10 men when Senad Lulic was sent off.
Being a man down did not put them off as Emir Spahic cut the deficit in the 65th, prompting Portugal to at last take the game by the scruff of the neck by scoring three goals in 10 minutes with two for Helder Postiga and one for Miguel Veloso.
Ireland had already done the hard work in their first leg and any lingering Estonian thoughts of a comeback were wiped out when Stephen Ward swept in a rebound.
Estonia got a 57th-minute consolation through Konstantin Vassiljev to make it 1-1 but the night belonged to the Irish, who will appear at their first major finals since the 2002 World Cup.