If Tsonga wins it doesn't matter the score-line. There are pros and cons to every scenario, can't definitively say which is the best outcome.
Tsonga wins, all Murray has to do is win on Friday.
Berdych wins, Murray has to win and that still might not be enough.
Of course if Berdych wins it means Andy would still have a small chance of qualifying should he lose on Friday, but do we really want to be looking at it like that?
Although Berdych winning would also give Murray a slim chance of topping the group, but given how tight it would be, he'd have just as much chance of coming 3rd.
He has to win on Friday regardless and Tsonga winning tonight would mean that would guarantee qualification, albeit in 2nd spot.