| Challenger Biella | 03/11 13:50 | 26 | [251] 라마신, 트리스탄 v 세피, 안드레아스 [107] | 6-1,1-6,6-7 | |
| Challenger Biella | 03/09 09:00 | 25 | [254] 그레니어, 휴고 v 라마신, 트리스탄 [251] | 4-6,2-6 | |
| Challenger Potchefstroom | 02/17 10:30 | 26 | [278] 쿠즈마노브, 디미탈 v 라마신, 트리스탄 [246] | 7-5,7-6 | |
| Challenger Potchefstroom | 02/15 12:25 | 25 | [253] 쿠이로즈, 로베르토 v 라마신, 트리스탄 [246] | 5-7,5-7 | |
| Challenger Potchefstroom | 02/10 08:00 | 26 | [220] 폴란스키, 페터 v 라마신, 트리스탄 [246] | 6-4,6-4 | |
| Challenger Potchefstroom | 02/08 09:30 | 25 | 라마신, 트리스탄 v Hunter, Vaughn | 7-6,1-6,6-1 | |
| Challenger Quimper | 02/01 09:30 | 19 | [245] 라마신, 트리스탄 v 캄케, 토비아스 [235] | 5-7,4-6 | |
| Challenger Quimper Qual | 01/31 09:00 | 14 | [215] 마르첸코, 일리아 v 라마신, 트리스탄 [249] | 0-6,6-4,6-7 | |
| Challenger Quimper | 01/26 18:55 | 25 | [249] 라마신, 트리스탄 v 코르다, 세바스티안 [103] | 6-7,6-4,6-7 | |
| Challenger Quimper | 01/25 09:30 | 19 | [216] 코필, 마리우스 v 라마신, 트리스탄 [249] | 3-6,4-6 | |
| Challenger Quimper | 01/24 12:05 | 14 | [249] 라마신, 트리스탄 v 그레니어, 휴고 [242] | 6-4,7-6 | |
| Antalya, Turkey | 01/10 08:00 | 26 | [271] 라마신, 트리스탄 v 버브릭, 알렉산더 [49] | 2-6,4-6 | |
| Antalya, Turkey | 01/08 07:00 | 25 | [271] 라마신, 트리스탄 v 게라시모브, 에고르 [78] | 7-6,6-2 | |
| Challenger Maia | 11/30 15:00 | 25 | [264] 라마신, 트리스탄 v 린더크네, 아서 [178] | 3-6,6-3,2-6 | |
| Challenger Parma 2 | 11/02 13:25 | 25 | 반니, 루카 v 라마신, 트리스탄 | 6-2,6-4 | |
| Challenger Parma 2 | 11/01 11:55 | 164 | 라마신, 트리스탄 v 기간트, 마테오 | 7-6,6-3 | |
| Challenger Parma 2 | 10/31 15:30 | 64 | 라마신, 트리스탄 v 코볼리, 플라비오 | 6-2,6-1 | |
| Marbella, Spain | 10/24 11:20 | 19 | [272] 라마신, 트리스탄 v 바란코 코사노, 자비엘 [312] | 0-6,6-7 | |
| Istanbul, Turkey | 10/21 07:30 | 26 | [128] 중, 제이슨 v 라마신, 트리스탄 [272] | 6-0,6-3 | |
| Istanbul, Turkey | 10/20 10:00 | 25 | [272] 라마신, 트리스탄 v 폴란스키, 페터 [211] | 4-6,6-2,7-5 | |
| Istanbul, Turkey | 10/18 10:00 | 164 | [242] 바투틴, 알렉세이 v 라마신, 트리스탄 [272] | 6-2,6-7,2-6 | |
| Istanbul, Turkey | 10/17 07:30 | 64 | 키르시, 코라이 v 라마신, 트리스탄 | 2-6,2-6 | |
| Lisbon, Portugal | 10/11 10:30 | 164 | [168] 오프넬, 세바스티안 v 라마신, 트리스탄 [271] | 6-4,6-3 | |
| Lisbon, Portugal | 10/10 09:00 | 64 | [301] 사카모토, 페드로 v 라마신, 트리스탄 [271] | 4-6,7-5,4-6 | |
| Challenger Barcelona | 10/03 08:30 | 26 | [271] 라마신, 트리스탄 v 폴란스키, 페터 [205] | 6-1,3-6,1-6 | |
| French Open, Paris, France | 09/23 12:05 | 15 | [172] 마르코라, 로베르토 v 라마신, 트리스탄 [268] | 7-6,3-6,6-3 | |
| French Open, Paris, France | 09/21 15:05 | 14 | [268] 라마신, 트리스탄 v 라마나단, 람쿠마르 [197] | 7-5,6-2 | |
| ITF M25 Plaisir | 09/15 13:35 | 25 | [268] 라마신, 트리스탄 v 헤이만, 크리스토펠 [390] | 3-6,6-7 | |
| Challenger Trieste | 08/22 09:00 | - | [265] 라마신, 트리스탄 v 보나디오, 리카르도 [409] | 4-6,2-6 | |
| Challenger Pau | 02/24 14:10 | 24 | [288] 코토브, 파벨 v 라마신, 트리스탄 [253] | 2-6,7-6,6-4 |
Tristan Lamasine (French pronunciation: [tʁistɑ̃ lamazin]; born 5 March 1993) is a French, professional tennis player.
Lamasine has a career-high ATP singles ranking of No. 181 achieved on 3 August 2015. He has a career-high ATP doubles ranking of No. 85 achieved on 13 June 2016.
From 2010 to 2015, Lamasine played mostly in the ATP Challenger Tour and the ITF Men's Circuit.
He made his ITF Men's Circuit singles debut (at a tournament in France) in September 2010 and ATP Challenger Tour singles debut (at the 2011 Challenger Banque Nationale de Rimouski) in March 2011.
From 2010 to 2015, Lamasine played in the singles event of only four ATP World Tour events (2011 Metz, 2014 Gstaad, 2014 Vienna and 2015 Marseille) and was eliminated in the singles qualifying rounds of all of them.
He made his ITF Men's Circuit doubles debut (at a tournament in France) in September 2010. In October 2011, he made his debut in the doubles event of an ATP Challenger Tour tournament, at the 2011 Open de Rennes.
Lamasine made his Grand Slam singles and men's doubles debut at the 2014 French Open. He was beaten in the second qualifying round of the men's singles. He and Laurent Lokoli, who had received a wild card for the men's doubles main draw, lost in the men's doubles first round to the 4th-seeded pair of David Marrero and Fernando Verdasco.
In July 2015, Lamasine reached his first career ATP Challenger Tour singles final at the tournament in Tampere. He defeated André Ghem in the final 6–3, 6–2.
Lamasine qualified for the singles main draw of 2016 Wimbledon Championships after winning three qualifying matches. He lost in the first round of the singles main draw to 25th seed Viktor Troicki in straight sets. It was his first career singles match in the main draw of an ATP World Tour or Grand Slam tournament.
Lamasine won two singles qualifying matches to reach the singles main draw of the 2016 Swedish Open, but lost in the first round to another qualifier, Calvin Hemery, in three sets. That was his first career singles match in the main draw of a non-Grand Slam ATP World Tour tournament.
Lamasine won two singles qualifying matches to reach the singles main draw of the 2016 Swiss Open. He went on to register his first career singles win in the main draw of an ATP World Tour tournament by defeating Radu Albot in straight sets in the first round. He lost his second-round match to third seed Albert Ramos-Viñolas in straight sets. At that tournament, Lamasine made his doubles debut in a non-Grand Slam ATP World Tour tournament by partnering Paul-Henri Mathieu; the unseeded pair lost in the first round of the main draw.
Starting from the first week of 2019, Lamasine played exclusively on the ATP Challenger Tour until the ATP Tour 250 Lyon Open that was held in late May. At the Lyon Open, Lamasine gained entry to the singles main draw as a lucky loser when Mikhail Kukushkin withdrew due to right shoulder pain. Lamasine had lost to Jannik Sinner in the final qualifying round but defeated him in main draw first round before losing to top seed Nikoloz Basilashvili in the second round.