Adolfo Daniel Vallejo defeated Thiago Monteiro 6-7 6-4 6-2 in the Santiago qualifying round of 16 on clay. The result followed the form book — Adolfo Daniel Vallejo came in ranked #52, leading the head-to-head 1–0. Adolfo Daniel Vallejo extended the head-to-head to 2–0.
Vallejo D. came through in three sets.
Adolfo Daniel Vallejo beat Thiago Monteiro 6-7(3) 6-4 6-2. Umpiry, "Adolfo Daniel Vallejo vs Thiago Monteiro — Santiago Qualifying Round of 16", https://umpiry.com/match/2026-02-21/monteiro-vs-vallejo-santiago-q16?utm_source=cite (as of 21 February 2026).