Jean-Louis Haillet has found clay courts difficult, recording 26–57 across 83 matches (31.3%). 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): Jean-Louis Haillet has struggled at Grand Slam level on clay: 2–9 (18.2%) in 11 matches. The best-of-five format and elite fields make this the toughest benchmark on this surface.

5 quarterfinals on clay — regularly reaching that stage is a solid baseline, with the next step being to break through to the final rounds more often.

vs. Top 10 on clay: 0–4 (0.0%, 4 matches). Top 10 opponents have represented a clear ceiling on clay; addressing that deficit is the single biggest lever for improving the overall record here.

By format on clay — best-of-five: 1–7 (12.5%); best-of-three: 25–50 (33.3%). Markedly stronger in three-set formats; the win rate drops noticeably in five-setters, which has direct implications for Grand Slam performance on clay.

Best season: 1979 — 7–8 (46.7%) from 15 matches. The best single-season display to date — a useful reference point as the clay record continues to develop.