Nadia Petrova defeated Shuai Peng 6-4 6-3 in the Bali quarter-final on hard. The upset overturned the form book — Shuai Peng came in leading the head-to-head 3–2, but Nadia Petrova had been the form player, winning 3 of their last 7 on hard. That levelled the head-to-head at 3–3.
Petrova N. took it in straight sets.
Petrova N. and Peng S. faced 8 of the same opponents in the last 12 months. Petrova N. went 6–6 (50%) against them, Peng S. 6–5 (55%). Results against comparable opponents are close (2 : 2 better-results split).
Hard: Petrova N. leads 3–2 · Clay: Peng S. leads 1–0
Nadia Petrova beat Shuai Peng 6-4 6-3. Umpiry, "Nadia Petrova vs Shuai Peng — Bali Quarter-final", https://umpiry.com/match/2011-11-03/peng-vs-petrova-bali-qf?utm_source=cite (as of 3 November 2011).