Ivanovic splits from coach Gunthardt

Former No. 1 Ana Ivanovic has announced she has split from coach Heinz Gunthardt despite a recent upturn in form.

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

However, Gunthardt was unable to travel with Ivanovic full time and that appears to have put paid to their working relationship.

The 22-year-old Serb said in a statement that she needs ''a full-time coach who is with me at all tournaments and during training periods.''

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