Juan Antonio Marin has found clay courts difficult, recording 71–91 across 162 matches (43.8%). The numbers point to a surface that has not consistently suited the game — a key area of opportunity on the calendar. Claimed 1 title on clay: Bastad.

At Grand Slam level (Roland Garros): Juan Antonio Marin has yet to record a win on clay at this stage — 0–5 across 5 Grand Slam matches. Breaking through here would mark a significant step forward on this surface.

2 finals reached on clay — won 1, lost 1 (solid 50% conversion) — consistently getting to finals and winning the majority is a hallmark of elite performers on clay. 7 semifinals. 16 quarterfinals.

vs. Top 10 on clay: 1–3 (25.0%, 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: 0–6 (0.0%); best-of-three: 71–85 (45.5%). Markedly stronger in three-set formats; the win rate drops noticeably in five-setters, which has direct implications for Grand Slam performance on clay.

Peak season: 1999 — 16–12 (57.1%) from 28 matches. That year captures the ceiling of what Juan Antonio Marin can do on clay when performing at their best and represents the standard to aim for.