Jan Hajek has found hard courts difficult, recording 8–39 across 47 matches (17.0%). 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 (Australian Open & US Open): Jan Hajek has struggled at Grand Slam level on hard: 2–8 (20.0%) in 10 matches. The best-of-five format and elite fields make this the toughest benchmark on this surface.

ATP Masters 1000 on hard (Indian Wells, Miami, Canada, Cincinnati, Shanghai, Paris): Jan Hajek has struggled at Masters level on hard: 0–4 (0.0%) in 4 matches. Improving at this level is the clearest path to a stronger overall record on this surface.

By format on hard — best-of-five: 2–10 (16.7%); best-of-three: 6–29 (17.1%). Consistent regardless of format on hard — a sign of a well-rounded game that holds up as matches develop.

Best season: 2010 — 4–11 (26.7%) from 15 matches. The best single-season display to date — a useful reference point as the hard record continues to develop.