Jelena Jankovic signed the exit visa for the last of the Williams sisters at the WTA Rome Masters as Maria Sharapova squeezed out another tight win to reach the semi-finals on Friday, dpa reported.
Fourth seed Jankovic produced a fightback over Venus Williams 5-7, 6- 2, 6-3. Sharapova came good in another struggle at the Foro Italico to post her seventh win from eight matches with the Swiss.
Only hours after Serena Williams had begged off her match with French teenager Alize Cornet due to a back problem, Serbia's fourth-seeded trophyholder Jankovic staked her claim on another Foro Italico title run.
Jankovic came back from a break down in the final set to overhaul the Venus, playing in her first event in nearly six weeks due to a still-unrevealed health problem.
"It was a tough match and I had to fight for every point," said the winner, who has been treated for breathing problems for the past week.
Second seed Sharapova was made to work by wily veteran Schnyder to set up a final four meeting with Jankovic, whom she has beaten on four of five occasions.
Serena Williams said she hit only a few shots in warm-up on a practise court prior to the back blockage which kept from her date on court with Cornet.
"I don't expect this to cause any problems with my preparation for the French," said Williams, who went to hospital for tests. "It just happened all of a sudden.
"I feel like I'm going to be good going into Roland Garros (starting a week from Sunday)."
Williams retired during matches three times in 2007, handing over a total of ten matches to opponents since 2001. She last quit against Anna Chakvetadze at the season-ending championships last November in Madrid.
The American beat number 34 Cornet in their only other meeting, last month in the Charleston semis on American green clay.
Cornet, an 18-year-old hope, will play on Saturday against off-the-boil sixth seed Chakvetadze.
The ragged Russian struggled into the final four with an unappetising 6-2, 3-6, 6-1, win over Bulgarian Tsvetana Pironkova.
"I don't know what happened, I felt like I was playing against myself," said the sixth seed after winning a low-standard contest marred by a combined 87 unforced errors.
The win in just under two hours end the giant-killing week of the 20-year-old Pironkova, who beat top seed Ana Ivanovic in the second round.
The Bulgarian ranked 64 has lifted her level this week after failing to win out of qualifying rounds three times this season.
Chakvetadze said she was troubled by a right shoulder, a complaint which also bothered her opponent.
The Russian took treatment but said that she felt a chill during that break which compromised her second set. "I was not there in the second set," she confessed. "I'm just glad I got through this match.
"In the second set I didn't feel that well and the shoulder was still bothering me."