You would expect that the coming together of two nations that went undefeated through qualification would be a headline match, yet that couldn't be further from the truth when Spain takes on Iran. FIFA's regional qualification guidelines make sense for several reasons, yet confederations like the AFC, CAF and CONCACAF will always find it hard to catch up with UEFA and CONMEBOL without more consistent fixtures against them.
Spain enter the tournament as one of the top ten nations in terms of the FIFA rankings, while Iran appear well down the list at 37th despite their almost flawless build up. The gulf between the two nations in the rankings will be apparent in the odds, as Spain enter as almost unbackable favourites to win this match.
So do Iran have a chance? They will likely have taken confidence from their opening match against Morocco, and perhaps the nerves will have settled as they enter their match against the 2010 champions. Yet this is a huge step up for the top-ranked Asian nation, and they will need to be at their defensive best to counter the incredible attacking depth that Spain possesses.
Neither side will underestimate the importance of this clash. As the second match of the group stage, each team will know that a loss here could derail their campaign completely. Iran desperately need to earn at least a point here as they next face European champions Portugal, while Spain perhaps won't be as desperate as they head into the final round to face Morocco. Could this be a factor in the match result?
Spain did lose two of their matches in the group stage of the last World Cup, which resulted in an early exit, although that was against Chile and the Netherlands. Surely Iran do not fall into the same category in terms of class.
It looks like the top sportsbooks agree. Spain enter this match as one of the shortest-priced favourites you will see at this World Cup. The Europeans start at -632, which is barely worth a bet, while the only other conceivable result is the draw, priced at +586. If you believe Iran can get the job done, you can take odds of +1800. You never know in football.
Surely though this one won't go any other way. If you're simply looking at the head to head market, Spain is the only option. We're predicting a low-scoring match, but a comfortable enough victory for Spain who will not concede in this fixture.