| ATP - Munich | 04/13 12:00 | 14 | [303] Alessandro Giannessi v Marc-Andrea Huesler [232] | 3-6,0-6 | |
| Challenger - Sarasota | 04/09 15:00 | 25 | Alessandro Giannessi v Hemery, Calvin | 4-6,6-2,2-6 | |
| Challenger - Mexique | 04/03 19:25 | 26 | [304] Aidan Mayo v Alessandro Giannessi [297] | 3-6,7-6,6-3 | |
| Challenger - Mexique | 04/01 21:45 | 25 | Alessandro Giannessi v Vasek Pospisil | 6-3,3-6,6-4 | |
| Challenger Naples | 03/25 09:00 | 19 | Alessandro Giannessi v Evan Furness | Retired | |
| Challenger Naples | 03/24 10:45 | 14 | Alessandro Giannessi v Fabrizio K P Osti | 6-3,6-1 | |
| Challenger - Zadar | 03/20 11:05 | 26 | [273] Timofey Skatov v Alessandro Giannessi [241] | 6-1,6-2 | |
| Challenger - Zadar | 03/18 12:30 | 25 | [241] Alessandro Giannessi v Corentin Moutet [107] | 5-7,6-2,6-4 | |
| Challenger Szekesfehervar | 03/13 11:25 | 26 | [234] Alessandro Giannessi v Matteo Martineau [190] | 4-6,6-7 | |
| Challenger Szekesfehervar | 03/11 12:25 | 25 | [234] Alessandro Giannessi v Mathias Bourgue [272] | 6-4,1-6,6-4 | |
| Challenger - Tenerife | 02/27 12:15 | 25 | [430] Carlos Lopez Montagud v Alessandro Giannessi [232] | Retired | |
| Challenger - Tenerife | 02/20 10:00 | 25 | [183] Matteo Gigante v Alessandro Giannessi [234] | 6-2,6-3 | |
| Challenger Manama | 02/13 08:00 | 25 | [234] Alessandro Giannessi v Damir Dzumhur [160] | 3-6,1-6 | |
| ATP - Cordoba | 02/03 15:50 | 14 | [135] Luciano Darderi v Alessandro Giannessi [223] | 6-2,6-0 | |
| Challenger - Piracicaba | 01/30 17:00 | 25 | [263] Gianluca Mager v Alessandro Giannessi [223] | Retired | |
| Challenger - Punta del Este | 01/23 16:00 | 25 | [138] Juan M Cerundolo v Alessandro Giannessi [226] | 1-6,6-4,6-1 | |
| Open d'Australie | 01/10 03:00 | 14 | [216] Alessandro Giannessi v John Millman [484] | 3-6,4-6 | |
| ATP Brisbane | 12/30 08:25 | 14 | [97] Alex Michelsen v Alessandro Giannessi [203] | 6-3,6-2 | |
| Challenger Maia | 11/28 10:30 | 25 | [206] Alessandro Giannessi v Henrique Rocha [255] | 4-6,7-6,2-6 | |
| Challenger Valencia | 11/22 11:45 | 26 | [212] Alessandro Giannessi v Albert Ramos-Vinolas [96] | 1-6,6-0,6-7 | |
| Challenger Valencia | 11/21 10:00 | 25 | [212] Alessandro Giannessi v Miguel Damas [417] | 6-2,6-4 | |
| Montevideo, Uruguay | 11/14 15:00 | 25 | [111] Facundo Diaz Acosta v Alessandro Giannessi [211] | 6-1,7-5 | |
| Challenger Lima | 11/08 18:30 | 26 | [217] Alessandro Giannessi v Daniel Elahi Galan [93] | 4-6,3-6 | |
| Challenger Lima | 11/07 17:45 | 25 | [217] Alessandro Giannessi v Oriol Roca Batalla [192] | 1-6,6-3,6-2 | |
| Challenger Olbia | 10/17 20:10 | 25 | [141] Lloyd Harris v Alessandro Giannessi [210] | 7-6,6-0 | |
| Lisbon, Portugal | 10/02 14:10 | 25 | [139] Pablo Llamas Ruiz v Alessandro Giannessi [213] | 6-3,6-1 | |
| Challenger Braga | 09/27 12:55 | 26 | [199] Duje Ajdukovic v Alessandro Giannessi [213] | 7-5,5-7,6-2 | |
| Challenger Braga | 09/26 14:00 | 25 | [351] Gastao Elias v Alessandro Giannessi [215] | 6-7,4-6 | |
| Challenger Sibiu | 09/19 10:20 | 25 | Bor Artnak v Alessandro Giannessi | Retired | |
| Challenger Seville | 09/07 19:00 | 27 | [244] Alessandro Giannessi v Hugo Gaston [99] | 6-3,1-6,0-6 |
Alessandro Giannessi (born 30 May 1990) is a professional Italian tennis player. On 24 July 2017 he reached his highest ATP singles ranking of world No. 84 while his best doubles ranking was No. 171 on 14 October 2013.
Giannessi made his Grand Slam debut at the 2016 US Open as a qualifier where he recorded his first Major win defeating Denis Kudla in five sets.
Giannessi was a singles semifinalist at the 2017 Croatia Open Umag.
At the 2021 French Open he made his debut at this Major after qualifying for the main draw with a win over Francisco Cerundolo.
At the 2022 French Open although he lost in the third round of qualifying to Sebastian Ofner he entered the main draw as a lucky loser.
He won his fourth Challenger title and first since 2019 at the 2023 Zadar Open this time with a win over Sebastian Ofner.