Dominic Thiem defeated Roberto Bautista Agut 6-4 6-3 in the St. Petersburg semi-final on carpet. The upset overturned the form book — Roberto Bautista Agut came in leading the head-to-head 3–0, defending last year's semi-final. Dominic Thiem claimed a first win over Roberto Bautista Agut in four meetings, narrowing the head-to-head to 3–1.
Thiem D. took it in straight sets.
Thiem D. and Bautista-Agut R. faced 6 of the same opponents in the last 12 months. Thiem D. went 3–4 (43%) against them, Bautista-Agut R. 1–6 (14%). Thiem D. came out better against 2 of 6 comparable opponents, Bautista-Agut R. against 0 — though 1 of those edges carries caveats (retirement).
Carpet: Thiem D. leads 1–0 · Hard: Bautista-Agut R. leads 3–0
Dominic Thiem beat Roberto Bautista Agut 6-4 6-3. Umpiry, "Dominic Thiem vs Roberto Bautista Agut — St. Petersburg Semi-final", https://umpiry.com/match/2018-09-17/agut-vs-thiem-st-petersburg-sf?utm_source=cite (as of 17 September 2018).