Vinci is really not doing anything at all. this is what a no backhand does, she has not a lot of ways to win a point, only forehand or drop shot. serve to her backhand second serve and you know she's not gonna hit a winner off it.
new haven-us-tokyo SF>4 mm W?
i dunno.
luckily she has both, so at this point, even without RG, her place in top10 is just as solid as the three girls below her.
if she makes another SF in beijing, she'll be fighting azarenka for a top4 seeding post miami.