|Full name||Kari Juhani Sundgren|
|Date of birth||25 October 1967|
|Place of birth||Vammala, Finland|
|Height||1.87 m (6 ft 1 1⁄2 in)|
|* Senior club appearances and goals counted for the domestic league only.
Sundgren was born in Vammala, Finland, but moved to Sweden with his parents as a toddler, being raised in Västerås. There, he was often called Gary and it caught on, being addressed in the latter manner for the duration of his career.
Sundgren started playing professionally with AIK Fotboll, being an undisputed starter from an early age. He scored the winner against Malmö FF when they became Swedish champions for the first time in 55 years, in 1992.
- Scores and results list Sweden's goal tally first.
|1.||16 February 1997||Supachalasai, Bangkok, Thailand||Thailand||1–0||3–1||1997 King's Cup|
Sundgren is the father of four children. One of his sons, Daniel, is also representing AIK, while his nephew Mikael Backlund spent several years with the Calgary Flames of the National Hockey League.
- "Gary Sundgren om övergången till Svanskog" [Gary Sundgren on the transition to Svanskog]. Värmlands Folkblad (in Swedish). 10 June 2015. Retrieved 10 June 2016.
- "Sundgren, primera alta maña" [Sundgren, first maño in]. Mundo Deportivo (in Spanish). 3 June 1997. Retrieved 10 June 2016.
- "Sweden name preliminary squad for Euro 2000". ESPN Soccernet. 18 May 2000. Retrieved 17 October 2014.
- Shaw, Phil (16 June 2000). "Larsson is unable to lift Sweden". The Independent. Archived from the original on 11 July 2000. Retrieved 17 October 2014.
- "Gary Sundgren". ESPN Soccernet. 13 July 2000. Retrieved 17 October 2014.
- "Backlund får inte kalla sig veteran: "Tränaren vill inte det"" [Backlund may not call himself a veteran: ”The coach does not want it”] (in Swedish). Viasat. 26 November 2015. Retrieved 10 June 2016.
- "Llegó el Frente y se fue el Atlético" [The Front arrived and Atlético left]. ABC (in Spanish). 21 June 2001. Retrieved 10 June 2016.
- "Zaragoza, no hay quinta Copa mala" [Zaragoza, no such thing as a bad fifth Cup]. ABC (in Spanish). 1 July 2001. Retrieved 10 June 2016.