Jorge Sampaoli's Argentina are through to the first knockout round after emerging from a tightly contested Group D.
Table-toppers Croatia were already guaranteed passage to the Round of 16 after winning their opening two matches, barring a miraculous mathematical turnaround.
After taking only one point from their opening two matches, Tuesday evening's showdown with Nigeria was an all-or-nothing encounter.
For the Nigerians, a berth in the knockout stages for the second World Cup in a row beckoned and, when Victor Moses' penalty was rolled in to equalise shortly after the break, it looked as though Argentina would be sent home early.
Marcos Rojo's strike with only minutes to spare saved the 2014 finalists' blushes as Lionel Messi and company now prepare to take on France on Saturday.