Deutsch 
| Position | Stürmer |
| Nationalität |  |
| Geburtsort | Bressanone, ITA |
| Größe | 183 cm |
| Gewicht | 82 kg |
| Geburtsdatum | 05.08.1992 |
| Jugendmannschaft | Gherdëina |
| Schläger | Rechts |
| Season | Team | League | GP | G | A | TP | PIM | Playoffs | GP | G | A | TP | PIM | |
| 2006-2007 | Gherdëina U19 | Italy U19 | 3 | 2 | 2 | 4 | 4 | | | Playoffs | 4 | 3 | 1 | 4 | 0 |
| 2007-2008 | Pikes Oberthurgau U17 | Swiss U18-Elit | 31 | 8 | 16 | 24 | 24 | | | Playoffs | 4 | 3 | 0 | 3 | 0 |
| 2008-2009 | Pikes Oberthurgau U17 | Swiss U18-Elit | 30 | 19 | 20 | 39 | 28 | | | Playoffs | 3 | 2 | 0 | 2 | 0 |
| Italy U18 | WJC-18 D1 | 5 | 0 | 0 | 0 | 2 | | | |||||||
| 2009-2010 | HC Lugano U21 | Swiss U21-Elit | 35 | 16 | 19 | 35 | 32 | | | Playoffs | 3 | 0 | 0 | 0 | 0 |
| Italy U18 | WJC-18 D2 | 5 | 4 | 7 | 11 | 2 | | | |||||||
| 2010-2011 | HC Lugano U21 | Swiss U21-Elit | 28 | 16 | 19 | 35 | 34 | | | Playoffs | 3 | 1 | 0 | 1 | 4 |
| Italy U20 | WJC-20 D1 | 5 | 1 | 2 | 3 | 2 | | | |||||||
| 2011-2012 | HC Lugano U21 | Swiss U21-Elit | 11 | 8 | 6 | 14 | 20 | | | ||||||
| HC Lugano | NL | 35 | 2 | 2 | 4 | 2 | | | |||||||
| Italy (all) | International | 1 | 0 | 0 | 0 | 0 | | | |||||||
| 2012-2013 | HC Lugano | NL | 50 | 6 | 8 | 14 | 8 | | | Playoffs | 7 | 0 | 0 | 0 | 0 |
| Italy | OGQ | 3 | 0 | 0 | 0 | 0 | | | |||||||
| Italy | WC D1A | 5 | 1 | 2 | 3 | 6 | | | |||||||
| Italy (all) | International | 15 | 2 | 3 | 5 | 10 | | | |||||||
| 2013-2014 | HC Lugano | NL | 41 | 6 | 13 | 19 | 16 | | | Playoffs | 5 | 0 | 0 | 0 | 0 |
| Italy | WC | 7 | 1 | 0 | 1 | 6 | | | |||||||
| Italy (all) | International | 9 | 1 | 1 | 2 | 8 | | | |||||||
| 2014-2015 | HC Lugano | NL | 36 | 3 | 7 | 10 | 20 | | | Playoffs | 6 | 1 | 2 | 3 | 2 |
| HC Lugano | Swiss Cup | 2 | 0 | 0 | 0 | 0 | | | |||||||
| Italy | WC D1A | 3 | 0 | 0 | 0 | 0 | | | |||||||
| Italy (all) | International | 5 | 1 | 0 | 1 | 0 | | | |||||||
| 2015-2016 | HC Lugano | NL | 46 | 1 | 3 | 4 | 8 | | | Playoffs | 14 | 1 | 1 | 2 | 0 |
| HC Lugano | Swiss Cup | 2 | 0 | 0 | 0 | 2 | | | |||||||
| HC Lugano | Spengler Cup | 3 | 0 | 0 | 0 | 0 | | | |||||||
| Italy | OGQ | 3 | 2 | 1 | 3 | 0 | | | |||||||
| Italy | WC D1A | 5 | 0 | 2 | 2 | 0 | | | |||||||
| Italy (all) | International | 12 | 2 | 3 | 5 | 2 | | | |||||||
| 2016-2017 | HC Ambrì-Piotta | NL | 41 | 1 | 3 | 4 | 18 | | | Relegation | 10 | 0 | 1 | 1 | 2 |
| HC Ambrì-Piotta | Swiss Cup | 1 | 0 | 0 | 0 | 2 | | | |||||||
| HC Ambrì-Piotta | NLA Q | - | - | - | - | - | | | Qualification | 4 | 2 | 0 | 2 | 0 | |
| Italy | OGQ | 3 | 1 | 0 | 1 | 4 | | | |||||||
| Italy | WC | 7 | 0 | 0 | 0 | 2 | | | |||||||
| Italy (all) | International | 16 | 1 | 2 | 3 | 10 | | | |||||||
| 2017-2018 | HC Ambrì-Piotta | NL | 50 | 12 | 4 | 16 | 20 | | | Relegation | 10 | 3 | 3 | 6 | 6 |
| HC Ambrì-Piotta | Swiss Cup | 2 | 0 | 0 | 0 | 0 | | | |||||||
| Italy | WC D1A | 4 | 2 | 2 | 4 | 0 | | | |||||||
| Italy (all) | International | 12 | 2 | 3 | 5 | 8 | | | |||||||
| 2018-2019 | HC Ambrì-Piotta | NL | 50 | 6 | 7 | 13 | 22 | | | Playoffs | 5 | 0 | 0 | 0 | 4 |
| HC Ambrì-Piotta | Swiss Cup | 3 | 0 | 1 | 1 | 2 | | | |||||||
| Italy | WC | 5 | 0 | 0 | 0 | 0 | | | |||||||
| Italy (all) | International | 10 | 1 | 1 | 2 | 0 | | | |||||||
| 2019-2020 | HC Ambrì-Piotta | NL | 1 | 1 | 0 | 1 | 0 | | | ||||||
| HC Ambrì-Piotta | Champions HL | 4 | 0 | 1 | 1 | 0 | | | |||||||
| HC Ambrì-Piotta | Swiss Cup | 1 | 0 | 1 | 1 | 0 | | | |||||||
| 2020-2021 | HC Ambrì-Piotta | NL | 50 | 9 | 14 | 23 | 12 | | | ||||||
| HC Ambrì-Piotta | Swiss Cup | 3 | 0 | 0 | 0 | 0 | | | |||||||
| 2021-2022 | HC Ambrì-Piotta | NL | 47 | 6 | 7 | 13 | 18 | | | Playoffs | 3 | 0 | 0 | 0 | 0 |
| Italy | OGQ | 3 | 0 | 0 | 0 | 0 | | | |||||||
| Italy | WC | 7 | 1 | 0 | 1 | 0 | | | |||||||
| Italy (all) | International | 12 | 1 | 0 | 1 | 4 | | | |||||||
| 2022-2023 | HC Ambrì-Piotta | NL | 29 | 1 | 3 | 4 | 10 | | | ||||||
| 2023-2024 | HC Ambrì-Piotta | NL | 32 | 5 | 4 | 9 | 12 | | | Playoffs | 4 | 0 | 1 | 1 | 0 |
| Italy | WC D1A | 5 | 3 | 1 | 4 | 0 | | | |||||||
| Italy (all) | International | 8 | 5 | 3 | 8 | 8 | | | |||||||
| 2024-2025 | HC Ambrì-Piotta | NL | 43 | 2 | 1 | 3 | 8 | | | Playoffs | 4 | 1 | 0 | 1 | 0 |
| Italy | WC D1A | 5 | 0 | 0 | 0 | 4 | | | |||||||
| Italy (all) | International | 12 | 1 | 2 | 3 | 10 | | | |||||||
| 2025-2026 | HC Ambrì-Piotta | NL | 27 | 1 | 2 | 3 | 6 | | | ||||||
| Italy | OG | - | - | - | - | - | | | |||||||
| Italy (all) | International | 2 | 0 | 0 | 0 | 2 | | |
Diego Kostner wurde am 5. August 1992 in Bressanone, Italien, geboren. Der 1,83 Meter große und 82 Kilogramm schwere Center entstammt dem Nachwuchs des HC Gherdëina, einem traditionsreichen Verein aus Südtirol. Mit seiner rechten Schusshand bringt er Übersicht, Spielintelligenz und technische Präzision ins Zentrum des Eises. Kostner ist bekannt für seine mannschaftsdienliche Spielweise, starke Defensivarbeit und konstante Leistung auf hohem Niveau. Als Führungsspieler mit internationaler Erfahrung zählt er zu den festen Größen im italienischen Eishockey. Seine Verlässlichkeit und Einsatzbereitschaft machen ihn zu einem wichtigen Bestandteil jeder Mannschaft.
