Her secondary school physical education teacher noticed Defterli's talent and convinced her parents that she had a football playing future.

[2][3][5][6] At Istanbul Dinarsu Spor, she played and experienced championships in the Turkish Women's First Football League.

In the 2000 season with Delta Mobilyaspor, Defterli finished with another league championship and her second Top Scorer title.

After playing one year on loan at Hatay Sanayispor,[7] she returned home to Istanbul and learned that the women's football leagues in Turkey would be dissolved.

In 2004, the Turkish women's national football player was accepted to join the squad of FSV Frankfurt.

[3] Defterli made her national-team debut in the UEFA Women's Euro 2001 qualifying match against the Greek team, which was held on December 18, 1999, in Karditsa, Greece.

[14] At the 2003 FIFA World Cup qualification (UEFA) – Group 8 round, she scored a goal against both Bosnia and Herzegovina and Hungary.

[19][20][21][22][23] She scored goals in the 2011 FIFA Women's World Cup qualification – UEFA Group 5 matches against both Malta and Austria.