Constantin Frantzen

Constantin Frantzen (born 16 March 1998) is a tennis player from Germany. Frantzen has a career-high singles ranking of No. 1226, and a career-high doubles ranking of No. 66.

Doubles

 * 🇫🇷 Pau (27 Feb 2023) – 🇫🇷 Dan Added / 🇫🇷 Albano Olivetti def. 🇬🇧 Julian Cash / 🇩🇪 Constantin Frantzen, 3–6, 6–1, [10–8].
 * Lugano (6 Mar 2023) – 🇧🇪 Zizou Bergs / David Pel def. 🇩🇪 Constantin Frantzen / 🇩🇪 Hendrik Jebens, 6–2, 7–6(8–6).
 * Biel/Bienne (20 Mar 2023) – 🇩🇪 Constantin Frantzen / 🇩🇪 Hendrik Jebens def. 🇷🇴 Victor Vlad Cornea / Franko Škugor, 6–2, 6–4.
 * 🇦🇹 Mauthausen (8 May 2023) – Romain Arneodo / 🇦🇹 Sam Weissborn def. 🇩🇪 Constantin Frantzen / 🇩🇪 Hendrik Jebens, 6–4, 6–2.
 * 🇩🇪 Heilbronn (5 Jun 2023) – 🇩🇪 Constantin Frantzen / 🇩🇪 Hendrik Jebens def. 🇷🇴 Victor Vlad Cornea / 🇦🇹 Philipp Oswald, 7–6(9–7), 6–4.
 * 🇫🇷 Lyon (12 Jun 2023) – 🇫🇷 Manuel Guinard / 🇫🇷 Grégoire Jacq def. 🇩🇪 Constantin Frantzen / 🇩🇪 Hendrik Jebens, 6–4, 2–6, [10–7].
 * 🇩🇪 Augsburg (21 Aug 2023) – 🇩🇪 Constantin Frantzen / 🇩🇪 Hendrik Jebens def. 🇫🇷 Constantin Bittoun Kouzmine / 🇺🇦 Volodymyr Uzhylovskyi, 6–2, 6–2.
 * 🇮🇹 Como (28 Aug 2023) – 🇩🇪 Constantin Frantzen / 🇩🇪 Hendrik Jebens def. 🇸🇪 Filip Bergevi / Mick Veldheer, 6–3, 6–4.
 * 🇦🇹 Bad Waltersdorf (18 Sep 2023) – 🇩🇪 Constantin Frantzen / 🇩🇪 Hendrik Jebens def. 🇮🇹 Marco Bortolotti / 🇮🇹 Francesco Passaro, 6–1, 6–2.
 * 🇫🇷 Orléans (25 Sep 2023) – 🇩🇪 Constantin Frantzen / 🇩🇪 Hendrik Jebens def. 🇬🇧 Henry Patten / 🇦🇺 John-Patrick Smith, 7–6(7–5), 7–6(14–12).
 * 🇫🇷 Metz (6 Nov 2023) – Hugo Nys / 🇵🇱 Jan Zieliński def. 🇩🇪 Hendrik Jebens / 🇩🇪 Constantin Frantzen, 6–4, 6–4.

All finals

 * Key
 * Italics – Indicates the player lost in the final.
 * † – Indicates a final not played.
 * Doubles
 * Grade 4 – 🇩🇪 Cadolzburg (16 Feb 2015), 🇩🇪 Mönchengladbach (15 Jul 2015), 🇨🇿 Véska (20 Jul 2015)