World number one Justine Henin made a problem-free return to the court on Thursday, beating Dinara Safina 6-4, 6-1 in her first match since winning the US Open.
Henin took a break of nearly a month after seeing off Svetlana Kuznetsova in New York for her seventh career Grand Slam title.
On Thursday it looked like she had never been away as she saw off the Russian Safina with ease to reach the quarter-finals of the Stuttgart Grand Prix.
Fifth seed Ana Ivanovic failed to join her though, bundled out 6-2, 1-6, 6-3 by Ukrainian qualifier Kateryna Bondarenko in the day's big upset.
Jelena Jankovic was in danger of suffering the same fate as her fellow Serb but the third seed fought her way out of trouble against Shahar Peer of Israel, coming through 4-6, 6-1, 6-3.
Henin took just a little time to warm up, eventually making the decisive break in game seven of the first set.
The Belgian broke again at the start of the second set and completed a comfortable win in 74 minutes.
"I had a nice long rest after the US Open and this was a very good first match back for me," Henin said on court.
Henin goes on to face the winner of the later match between Daniela Hantuchova and Elena Dementieva.
SHOCK RESULT
The performance of the day came from Bondarenko, who described victory over Ivanovic as the best of her career.
Ivanovic lost her first service game and, although she broke back, never looked comfortable against Bondarenko's heavy returns.
The Ukrainian reeled off four games from 2-2 to clinch the first set before Ivanovic upped her game in the second.
The deciding set stayed with serve until game eight when Ivanovic smacked an attempted forehand winner into the net.
Bondarenko made two bad mistakes on her first couple of match points but an unforced error from the Serb saw her home.
"I wasn't surprised," said Bondarenko, who next faces Frenchwoman Tatiana Golovin. "At the beginning I was nervous but I tried to focus and it went my way."
Holder Nadia Petrova beat Dutch qualifier Michaella Krajicek 6-1, 6-3 to book a quarter-final against Jankovic.
Friday's other quarter-final will be between Serena Williams and Kuznetsova.