What with Nishikori's withdrawal, Berdych's upset and Murray and Ferrer being the top two seeds left in the draw, it really puts the pressure right back on the first two who seemed all but safe before today.
Murray needs to make the win the tournament to surpass Berdych in the race, as I make it he'll only make up 210 points if he makes the final (300 - 90 for Rotterdam), leaving him 10 behind.
Ferrer will jump above Murray if he wins the tournament, even if Andy makes the final.
Big week this. Raonic could make big ground if he makes the final in Basel (Young, Goffin and a seemingly slightly-more-in-shape Nadal stand in his way), whilst Dimitrov will probably have to beat Federer in the QFs to make significant gains.
It's much more open in Valencia, so Murray really needs to be winning the whole thing - this would not only prevent Ferrer from making big gains and leaping him, but also propel himself away from the other contenders. If he doesn't, we can only hope Ferrer doesn't win the whole thing.
As it stands (points in brackets is how many they will have if they beat respective opponent):
5 Nishikori 4265 - WITHDREW
6 Cilic 4150 - Qualified
7 Berdych 4105 - OUT
8 Murray 3885 - Valencia R2 - route is Fognini (3885) - Anderson (3975) - Ferrer (4095) - Lopez/Dolgopolov/Robredo (4295)
9 Raonic 3795 - Basel R2 - route is Young (3840) - Goffin (3930) - Nadal (4050) - Federer (4250)
10 Ferrer 3775 - Valencia R2 - route is Verdasco (3775) - Bautista/Bellucci (3865) - Murray (3985) - Lopez/Dolgopolov/Robredo (4185)
11 Dimitrov 3555 - Basel R1 - route is Zverev (3555) - Pospisil (3555) - Federer (3645) - Karlovic (3765) - Nadal/Raonic (3965)