Christophe Casa has found clay courts difficult, recording 15–27 across 42 matches (35.7%). The numbers point to a surface that has not consistently suited the game — a key area of opportunity on the calendar.

At Grand Slam level (Roland Garros): Christophe Casa is 2–3 (40.0%) across 5 Grand Slam matches — below .500, though the elite draw depth at the Slams makes that a notoriously difficult barrier to crack.

By format on clay — best-of-five: 2–3 (40.0%); best-of-three: 13–24 (35.1%). Slightly better in five-set matches on clay — a positive sign for the Slams specifically.

Best season: 1977 — 3–5 (37.5%) from 8 matches. The best single-season display to date — a useful reference point as the clay record continues to develop.