Carina Witthoeft advanced when Petra Martic retired 4-6 4-1 in the New Haven qualifying round 1.
Witthoeft C. advanced when Martic P. retired.
Witthoeft C. and Martic P. faced 5 of the same opponents in the last 12 months. Witthoeft C. went 2–5 (29%) against them, Martic P. 1–4 (20%). Results against comparable opponents are close (0 : 1 better-results split).
Carina Witthoeft beat Petra Martic 4-6 4-1 after Petra Martic retired. Umpiry, "Carina Witthoeft vs Petra Martic — New Haven Qualifying Round 1", https://umpiry.com/match/2018-08-20/martic-vs-witthoeft-new-haven-q1?utm_source=cite (as of 20 August 2018).