World champions Germany seek a place in the last 16 of Euro 2016 on Tuesday when Croatia also hope to advance by shaking off their recent nightmare.
The Germans top Group C with four points owing to a better goal difference than Poland, with Northern Ireland third on three and Ukraine eliminated on zero points.
Poland play Ukraine in the final round of matches while the Germans meet Northern Ireland, needing just a draw to make absolutely sure of progressing but determined to win the game and the group.
Group D, playing later Tuesday, has title holders Spain already through with six points while Croatia have four, Czech Republic one and Turkey zero.
Croatia squandered a two-goal lead in a 2-2 draw with the Czechs as they were partly undone by the violent behaviour of their own fans fighting each other Friday.
Croatia now face 2008 and 2012 winners Spain, who trounced Turkey 3-0 in an indication of rising form, while Turkey's only chance to stay alive is by beating the Czechs.
The four best third-placed teams from the six groups also go through but these will not be known until the end of the group stage Wednesday.
In this respect Germany could possibly even afford to lose against Northern Ireland and advance. But that is not the plan for Die Mannschaft which has struggled up front showed little danger up front in the opening 2-0 over Ukraine and 0-0 with Poland.
"We want to win against Northern Ireland and we will win," coach Joachim Loew said.
Germany have won all four last group games in the Loew era, and their only two defeats in 14 matches against Northern Ireland date back a while to qualifying for Euro 1984.
Croatia were seconds from qualifying for the last 16 when the Czechs levelled with a late penalty after the incidents involving the Croatian fans which saw the game stopped for several minutes in the 87th minute.