Marsel Ilhan has found grass courts difficult, recording 4–8 across 12 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): Marsel Ilhan 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 grass — best-of-five: 2–4 (33.3%); best-of-three: 2–4 (33.3%). Consistent regardless of format on grass — a sign of a well-rounded game that holds up as matches develop.