Martin Vassallo Arguello has found hard courts difficult, recording 4–23 across 27 matches (14.8%). 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): Martin Vassallo Arguello has yet to record a win on hard at this stage — 0–7 across 7 Grand Slam matches. Breaking through here would mark a significant step forward on this surface.

ATP Masters 1000 on hard (Indian Wells, Miami, Canada, Cincinnati, Shanghai, Paris): Martin Vassallo Arguello is 3–5 (37.5%) across 8 Masters matches — below .500 in the Tour's deepest fields. Lifting that record here would unlock better results across the whole hard swing.

vs. Top 10 on hard: 0–4 (0.0%, 4 matches). Top 10 opponents have represented a clear ceiling on hard; addressing that deficit is the single biggest lever for improving the overall record here.

By format on hard — best-of-five: 0–7 (0.0%); best-of-three: 4–16 (20.0%). Markedly stronger in three-set formats; the win rate drops noticeably in five-setters, which has direct implications for Grand Slam performance on hard.

Best season: 2009 — 3–12 (20.0%) from 15 matches. The best single-season display to date — a useful reference point as the hard record continues to develop.