I see Del Potro and Simon won again today and are into their respective semi finals in Basel and Lyon.
They have both now overtaken Ferrer in the ATP race, to lie 7th and 8th.
Given they are also form players, I think the now current top 8 would be the best field for Shanghai :
Nadal, Federer, Djokovic, Murray, Davydenko, Roddick. Del Potro and Simon.
There are still other players in contention, including clearly Ferrer. But the more Del Potro and Simon win, the more difficult it will be for anyone else to get into the top 8.
It is though still certainly possible for Tsonga to make it.
Points in Paris are winner 100, finalist 70, semi finalist 45.
First 5 are sure of their place.
Then 6th to 11th are : Roddick 369, Del Potro 354, Simon 341, Ferrer 338, Blake 310, Wawrinka 301.
Tsonga is 12th on 290 points, so he would need to at least reach the final in Paris and other results go his way.
In theory there are still 14 players still chasing the remaining 3 spots, right down to Andreev on 242 points. Don't know what they'ed do if Simon and Andreev tied 8th on 342 points !!
Nalby will also go to 290 points if he beats Roger tomorrow, and remember that he did win Paris last year.
Actually I've just realised ( if I've done my sums right ! ) that if Tsonga wins the title in Paris next week, he will qualify for Shanghai.
1) Simon, Ferrer and Tsonga are all in the bottom half of the draw. If Tsonga wins the tournament he goes to 390 points. Simon and Ferrer being in the same half of the draw must then be at best semi finalists, and get a maximum of 45 points, therefore would not reach 390 points.
2) Everyone from Blake in 10th place down has 310 points or less. If Tsonga wins the tournament, the maximum any of them can get is 70 for being losing finalist. So they too can't reach 390 points.
So, win in Paris, he's in Shanghai ! Losing finalist and he's got a chance.
So, Roddick beats Simple Simon and Nalbandian beats Del Potro.
As a result, Roddick has booked his ticket to Shanghai, and both Del Potro and ( more so ) Simon are now waiting in hope that others don't nick their tickets.
Del Potro is on 369 points, Simon on 356 points.
Remaining contenders are :
Blake - needs to reach final, and that would do it for him. Tsonga - winning tournament would do it for him, reaching final might. Nalbandian - needs to win tournament, which would do it for him. Verdasco - needs to win tournament, and hope re other results. Monfils - needs to win tournament and hope re other results.
3 contenders remain to nick these Shanghai places from Del Potro and Simon.
Blake - quarter final opponent is Federer Tsonga - quarter final oponent is Roddick Nalbandian - quarter final opponent is Murray
Del Potro, in particular, must be getting ready to book that ticket. The only event that will prevent him going is : Nalbandian beats Blake in the final
Of course we mustn't forget that one or two people usually pull out of the Masters Cup and eventually some unknown Russian Kazakh who was 490th on the ALTS list will get drafted in because everyone else is on holiday
So, Blake, Tsonga and Nalbandian have all reached the semi finals on a shock day in Paris.
Assuming, all who qualify, now go to Shanghai ( I'm not quite sure how ailing Federer and Nadal are ? ), then :
Simon will no longer qualify, because the winner of the Blake / Tsonga semi final will overtake him.
If Blake wins that semi final, he will qualify for Shanghai.
If Tsonga wins that semi final, he will qualify for Shanghai, as long as he doesn't lose to Nalbandian in the final, in which case Nalbandian will qualify instead.
Nalbandian needs to win the tournament, in which case he will qualify.
If Nalbandian beats Blake in the final, both of these qualify, and it is the one scenario in which Del Potro wouldn't qualify.
By the way, as an incidental point, how much of a jammy sod does James Blake continue to be.
He seems to hardly ever beat anyone of particular merit, manages to lose to folk of insignificant merit, yet somehow hangs around about the top 10, and is now just a win away fom qualifying for Shanghai, thanks to Roger pulling out of Paris.
I already had this impression of good luck before Akhenaten did his special rankings, which take account mainly of the ranking of who players beat and lose to, plus some other factors.
And in July, James Blake was ranked 23rd !
Basically, I really hope Tsonga beats him, although I am afraid Nalbandian could beat Tsonga in the final.
In spite of him daring to beat Andy in the Aussie Open at the begininng of this year, I wouldn't mind Tsonga picking up a good few ranking points and qualifying for Shanghai.
He was injured for quite a few months, missing potential ranking points, plus if he doesn't do too well at the upcoming Aussie Open, when defending his final points from last year, he will take a big slide down the rankings. So go, JWT !
As you say the winner of Nalbandian v Tsonga will now be the 8th player to qualify. Tsonga has ovettaken Simon, but Nalby will overtake him in turn if he wins the tournament.
Actually, either of these, particulary Nalbandian in his current form, I think poses more of a danger in Shanghia than Simple would have.