Jankovic has been within sight of top spot for the last few weeks
Serbia's Jelena Jankovic will become world number one for the first time on 11 August, the WTA has confirmed.
The 23-year-old will replace her compatriot, Ana Ivanovic, who took top spot on 9 June.
Jankovic looked to have missed her chance with a surprise loss to Dominika Cibulkova in Montreal on Friday.
That defeat stopped her from taking over the number one position on 4 August, but she will have an eight-point lead by the following week.
Jankovic will have 3,620 points to Ivanovic's 3,612 on 11 August, making her the 18th world number one in the history of the WTA Tour.
"Since I was a young girl it's been my dream to become number one in the world," said Jankovic.
"When you get older, at least one day you can say you were number one and no one can take that away from you. You are in the Sony Ericsson WTA Tour history books and it's a great achievement."