Ana Ivanovic splits from coach

LONDON -- Former No. 1 Ana Ivanovic has split from coach Heinz Gunthardt despite a recent improvement in form.

Ivanovic has been working with Steffi Graf's former coach since March, rising to 24th in the rankings from 58th and ending a two-year title drought in Linz last month.

Gunthardt, however, was unable to travel with Ivanovic full time and the 22-year-old Serb said in a statement Monday that she needs "a full-time coach who is with me at all tournaments and during training periods."

Ivanovic has struggled with form and confidence since winning her only Grand Slam title at the French Open in 2008 and claiming the No. 1 ranking.