Brondello played for 10 seasons in the WNBL, reaching the playoffs on three occasions and being named Most Valuable Player in 1995 as a member of the Brisbane Blazers.

She also played between 1992 and 2002 in Germany for BTV Wuppertal, winning ten national championships and the 1995–96 FIBA Women's European Champions Cup.

She was selected by the Indiana Fever in late 1999's expansion draft, but never played a game for them, being traded to the Miami Sol along with a first-round pick for Stephanie White.

After sitting out of the 2002 season due to a foot injury playing for Wuppertal during the WNBA offseason,[5] Brondello signed as a free agent with the Seattle Storm in 2003, joining fellow Australians Lauren Jackson and Tully Bevilaqua.

[9] Brondello and her husband, associate head coach Olaf Lange, were fired by the Silver Stars in September 2010.

General manager Dan Hughes regained the title of head coach in January 2011, returning to the dual role he held before promoting Brondello.

[15] On 6 December 2021, the Phoenix Mercury announced that the team and head coach Sandy Brondello had mutually agreed to part ways and that her contract, which expired after the 2021 season, would not be renewed.

At the 2018 FIBA Women's Basketball World Cup held in Tenerife in Spain, the Australian team were runner-up beaten by the US 73-56 in the final.