BIRIMINGHAM, England (AP) -- Ana Ivanovic's winning start to the grass-court season was healthy enough to raise hopes that she will at last remedy her Wimbledon ills.

The former world No. 1 from Serbia looked worth her top seeding as she hurried past Mona Barthel, a tripwire opponent in the past, and into the third round of the Aegon Classic on Tuesday.

Ivanovic's hard-hitting 6-4, 6-1 win over the German had such a high ratio of winners it was hard to believe she has only once reached a Wimbledon semifinal and five times failed to reach the last 16.

''I haven't had the most success on grass,'' admitted Ivanovic, who has two weeks before Wimbledon to adapt herself to the vagaries of this surface.

''I really hope I manage to turn that around. On grass courts it's a lot about mentality and also the gameplan, because everything happens so fast.

''It's the first time I am working with my coach (Nemanja Kontic) on grass, so hopefully he can bring some innovations that will help me make that change.''

If he did, they certainly succeeded against Barthel, against whom Ivanovic had lost two of their three previous encounters. She worked hard to get lower on the green, lush surface, to hit flatter through the ball, and to move forward more often.

She also took more risks. These helped avoid going 3-0 behind, to recover well from 3-1 down, and take eight of the next nine games.

She next plays Victoria Duval, an American qualifier, and could play Sam Stosur, the former U.S. Open champion, in Sunday's final.

However, Ivanovic might have to survive a semifinal against Sloane Stephens, the U.S. Fed Cup player, while Stosur should have a quarterfinal with Daniela Hantuchova, the titleholder from Slovakia, who began impressively with a 6-1, 6-4 win over Belinda Bencic, the Wimbledon junior champion from Switzerland.