Halfway through the knockout we’ve got the following:
Group A
1A: Uruguay!!
2A: Mexico!
Out: S. Africa, France!!
Group B
1B: Argentina
2B: S. Korea
Out: Nigeria, Greece
Group C
1C: USA!!
2C: England
Out: Algeria, Slovenia
Group D
1D: Germany
2D: Ghana
Out: Serbia, Australia
So, the first half of the games in the Quarterfinals are (with FIFA rank)
Uruguay (16) v S. Korea (47)
USA (14) v Ghana (32)
Germany (6) v England (8)
Argentina (7) v Mexico (17)
The only game where I don’t have an easy favorite is Argentina v Mexico.