Martin Vassallo Arguello has found clay courts difficult, recording 41–53 across 94 matches (43.6%). 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): Martin Vassallo Arguello is 6–5 (54.5%) across 11 Grand Slam matches — below .500, though the elite draw depth at the Slams makes that a notoriously difficult barrier to crack.

ATP Masters 1000 on clay (Monte Carlo, Madrid, Rome): Martin Vassallo Arguello has struggled at Masters level on clay: 1–2 (33.3%) in 3 matches. Improving at this level is the clearest path to a stronger overall record on this surface.

2 semifinals on clay without yet reaching a final — consistent deep runs that show the ability to string together wins across a full draw, with the step to the final still to come. 5 quarterfinals adds further depth to that picture.

By format on clay — best-of-five: 6–5 (54.5%); best-of-three: 35–48 (42.2%). Significantly better in five-set matches — a strong physical profile on clay that tends to tell as matches and tournaments progress.

Best season: 2006 — 9–6 (60.0%) from 15 matches. The best single-season display to date — a useful reference point as the clay record continues to develop.