Jun Kuki has found grass courts difficult, recording 12–24 across 36 matches (33.3%). 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 (Wimbledon): Jun Kuki has struggled at Grand Slam level on grass: 2–9 (18.2%) in 11 matches. The best-of-five format and elite fields make this the toughest benchmark on this surface.

By format on grass — best-of-five: 3–12 (20.0%); best-of-three: 9–12 (42.9%). Markedly stronger in three-set formats; the win rate drops noticeably in five-setters, which has direct implications for Grand Slam performance on grass.

Best season: 1972 — 5–6 (45.5%) from 11 matches. The best single-season display to date — a useful reference point as the grass record continues to develop.