Rome :World number one Serena Williams had few problems in dismissing Russia's Maria Kirilenko 6-1, 6-4 on Thursday to reach the semi-finals of the Rome Open.
There she could face world number four and sister Venus, who plays seventh seed Jelena Jankovic of Serbia in the last of the day's quarter-finals.
Serena looked set for a particularly short afternoon as she took 10 of the first 11 games against her 37th ranked opponent, who had taken her to three sets as a teenager at Roland Garros six years ago.
But Kirilenko rallied to win three games in a row as Serena's forehand went to pot.
She steadied herself to hold at 4-3 and then served out the match despite her unforced error count creeping up at the end.
But having smashed down eight aces and 19 outright winners, her 18 unforced errors did not stop her advancing.
Playing in her first tournament since winning the Australian Open in January, Serena admitted her clay form has surprised her.
"I can't believe I'm still in the competition," she said.
Last year she was knocked out here in her first match, one of three opening match defeats in a row ahead of the French Open, where she reached the quarter-finals.
Earlier, Spain's Maria Martinez-Sanchez continued her fine run here as she beat the Czech Republic's Lucie Safarova 7-6 (8/6), 6-4.
The 27-year-old reached her second semi-final of the season as she looks to add to her only two career titles from last year in Bogota and Bastad.
Martin-Sanchez, ranked 26 in the world, had already shocked world number two Caroline Wozniacki of Denmark in the previous round.
Last year she caused a stir here when she almost beat then world number one Dinara Safina before falling away in the third set.
Martinez-Sanchez edged the first set 8-6 in the tie-break and initially looked to be cruising in the second went she went up two breaks but 35th-ranked Safarova hit straight back to level at 4-4.
The Spaniard broke again though and then served out the match to love.
She will face either former world number one and French Open champion Ana Ivanovic or 14th seed Nadia Petrova in the last four.