Tom Carnduff looks over the Group B action on Monday evening, and is backing Spain and Portugal to progress to the round of 16.
2pts Portugal to beat Iran by one goal at 63/25
1pt David Silva to be FIFA Man of the Match in Spain v Morocco at 4/1
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A Portugal win or draw against Iran would put them through. Spain face the same situation against Morocco but could also lose and still qualify as long as Portugal win. If both lose, and by the same scoreline, then fair play records or even drawing of lots could be needed to determine who qualifies.
It's winner takes all in Saransk as three points for either side will be enough to see them progress to the round of 16.
As expected at this stage, Portugal trail Spain in the standings and will be backed to win here, but it will be far from easy.
Iran's last seven games have been won by a single goal margin, with five of those games finishing 1-0, and there is value in backing another low-scoring affair here.
A best price of 63/25 is available on Portugal to win the game by one goal, and that looks tempting based on what we've seen of the opposition in their first two games.
Iran will want to be tough to get past, but they can't settle for anything less than a win, and that could present Portugal with goal-scoring opportunities.
Add in the fact that two of Portugal's last three victories have been by the single goal, and you can see why that sticks out as the best bet for this encounter.
Cristiano Ronaldo has once again been a star for Portugal and it'll come as little surprise to see him strike again here. That's reflected in the odds-on prices available on him to score.
The Real Madrid man is now 2/1 to win the Golden Boot, narrowly ahead of Belgium's Romelu Lukaku despite both being on four goals.
He'll be looking to lead by example once again here, but it won't be as comfortable for Ronaldo as it has been in their last two outings.
Score prediction: Iran 0-1 Portugal (Sky Bet odds: 7/2)
Best bet: Portugal to win the game by one goal at 63/25
Morocco are one of the sides who have already been eliminated from the World Cup, and Spain need a single point for progression in Kaliningrad.
Spain should have plenty of opportunities for attack here, and whilst Diego Costa has been firing them in up front, I'd be looking at the creative midfielders to shine in this contest.
That's why their could be value in backing a Man of the Match pre-game, and for me David Silva could be the star of the show.
Silva has had another great season in a dominant Manchester City side, scoring ten goals and assisting a further 14 in all competitions.
He played the majority of the 3-3 draw against Portugal, whilst featuring for the entire game in the narrow 1-0 victory over Iran. Spain need a result and will put out a strong outfit, where Silva should once again play a large part in the encounter.
Morocco have lost both of their two games so far by a single goal, and will be maybe feeling a little hard done-by that they have been sent packing already.
Spain though, will want to use this game to not only secure a spot in the knockout stages, but to also justify their joint-favourites tag and Morocco are in serious danger of going home having failed to score a single goal.
Fernando Hierro's men are around the even money mark to win to nil, which looks considerable better value than their 1/3 pre-match tag for victory.
Spain to win by two goals is also available at 3/1 if backing winning margins is more your thing, which looks the most realistic option to me in that market.
Score prediction: Spain 2-0 Morocco (Sky Bet odds: 9/2)
Best bet: David Silva to be FIFA Man of the Match at 4/1
Preview posted at 1635 BST (24/06/18)