John Bartlett has found clay courts difficult, recording 12–45 across 57 matches (21.1%). 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): John Bartlett has struggled at Grand Slam level on clay: 1–5 (16.7%) in 6 matches. The best-of-five format and elite fields make this the toughest benchmark on this surface.

vs. Top 10 on clay: 0–3 (0.0%, 3 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: 2–8 (20.0%); best-of-three: 10–37 (21.3%). Consistent regardless of format on clay — a sign of a well-rounded game that holds up as matches develop.

Best season: 1976 — 3–12 (20.0%) from 15 matches. The best single-season display to date — a useful reference point as the clay record continues to develop.