Argentina is the big favorite in Group F
Barring a major upset at the World Cup, Argentina will finish at the top of Group F and let the other three teams compete for second place.
On paper, not much separates African champion Nigeria and Bosnia, while Iran appears to be the long shot to earn a place in the round of 16.
Here are five things to know about Group F:
This is Nigeria's fifth World Cup and the fourth time they have been put in the same group as Argentina.
The South Americans have won each encounter so far by a single goal, including a 1-0 victory in 2010.
Argentina also came out ahead when the two nations met in the 2008 Olympic final.
Lionel Messi, Gonzalo Higuain, Angel Di Maria and Sergio Aguero - Argentina coach Alejandro Sabella has more attacking talent than he can fit into the lineup.
By comparison, the defense doesn't look quite as impressive.
Still, concerns about Argentina's vulnerability in the back shouldn't be exaggerated. The team conceded only 15 goals in 16 qualifying matches.
Of the 32 countries in the tournament, only Bosnia is making its first World Cup appearance.
Bosnia coach Safet Susic has seen World Cup action before, though. As a player he participated in the 1982 and 1990 tournaments for Yugoslavia.
IRAN'S SET PIECES
Iran isn't likely to rattle its opponents with technical brilliance, but watch out for set pieces.
Of the 30 goals the Iranians scored in qualifying, nine came on corner kicks or free kicks.
Bosnia also scored 30 goals in World Cup qualifying, but in only 10 matches (Iran played 16).
Manchester City striker Edin Dzeko accounted for one-third of Bosnia's tally, scoring 10 goals. Only Robin van Persie of the Netherlands scored more goals in the European qualifying groups with 11.