Uruguay - Portugal: Portugal wins. Uruguay is probably favoured going into the game because of 9/9 and no goals conceded in group stage, but on the other hand they had an easier group than Portugal. I still believe Portugal to take it with some Ronaldo magic.
France - Argentina: France wins. You never know what kind of Argentina is gonna show up, but the same can be said about France. Both of them didn't play a convincing group stage. Yes France got 7/9 but they didn't play great football. I still think Argentina used up all their luck this run and France will be a step too far.
Brazil - Mexico: Brazil wins. Mexico has been knocked out in the round of 16 in each of the past 6 World Cups and this will not be any different. After getting crushed 0-3 by Sweden I don't give them any chance anymore.
Belgium - Japan: Belgium wins. In November last year we played a friendly against Japan and won 1-0. Japan has yet to impress this World Cup and going up against the Belgian superstar team will be a very tough task. Keisuke Honda is one of my favourite players and it will be sad to see the tears rolling from his eyes after getting crushed.
Spain - Russia: Spain wins. Spain's attack looked very unconvincing aside from their game vs Portugal, but Russia's early easy wins were kind of a meme after they got crushed by Uruguay. Spain will take it after another unconvincing game. 1-0 proably.
Croatia - Denmark: Croatia wins: Croatia was one of the few teams to impress in the group stage and they got a beatable opponent in Denmark. Denmark does play organised but Croatia will take it with top class football.
Sweden vs Switzerland: Switzerland wins. Really even game, tough to call. Switzerland impressed me vs Brazil so I give them a slight edge but it might go eitherway.
Colombia vs England: England wins. It's a game that could go eitherway but James Rodriguez is probably out with a calf injury so I'd put my money on England.