Guy Den Ouden defeated Ryota Tanuma 7-5 6-3 in the M15 Monastir 37 quarter-final on hard. The upset overturned the form book — Ryota Tanuma came in leading the head-to-head 1–0. Guy Den Ouden claimed a first win over Ryota Tanuma in two meetings, levelling the head-to-head at 1–1.
Den Ouden G. took it in straight sets.
Guy Den Ouden beat Ryota Tanuma 7-5 6-3. Umpiry, "Guy Den Ouden vs Ryota Tanuma — M15 Monastir 37 Quarter-final", https://umpiry.com/match/2021-10-01/ouden-vs-tanuma-m15-monastir-37-qf?utm_source=cite (as of 1 October 2021).