Serena Williams battered Anastasia Pavlyuchenkova 6-4, 6-4 in the quarter-finals at Wimbledon on Tuesday, seizing on moments of weakness from the Russian to ram home her advantage.
The defending champion, seeking an elusive 22nd grand slam to equal Steffi Graf's open-era record, took the first set after finding a chink in her opponent's serving armoury in the ninth game.
Pavlyuchenkova, the 21st seed, went for her shots but never found a way to counter the Williams attack. Nerves told again in the same game of the second set, where a series of errors allowed the American to break and then serve for the match.
The world No.1 wrapped up the tie on her second match point with a 123 mph ace for 11 in total.
Williams joins her sister Venus in the semi-finals on Thursday where she will meet another Russian, Elena Vesnina.
"We are playing doubles later so we are just so glad to both get through to the semi-finals," Williams said.
Venus outguns Shvedova
Earlier, Venus vanquished Yaroslava Shvedova 7-6(5), 6-2 in a brutal baseline shootout to reach her first Grand Slam semi-final for six years.
In a scrappy match, the five-times champion - the oldest woman in the draw at 36 - drew on her experience to see off the Kazakh player contesting her first Wimbledon quarter-final.
There was little to choose between the two as they slugged it out in the first set, with neither finding much rhythm.
But Shvedova's challenge crumbled after she narrowly lost a tiebreak she had led 5-2.
The 28-year-old, ranked 96, made a string of errors in the second set while her seasoned American opponent - sensing her opportunity - found her range and produced a succession of winners off both flanks.
Williams, the 8th seed, advances to her first Grand Slam semi-final since the 2010 US Open and will face Germany's fourth-seeded Kerber.
The American said she was delighted with the quarter-final victory.
"If you are Serena Williams, this happens a lot - but as Venus Williams, this is an awesome day," she said referring to her sister, the world number one.
Berdych bests Czech mate
Tomas Berdych won a fifth-set shootout over Czech compatriot Jiri Vesely for a 4-6, 6-3, 7-6(8), 6-7(9), 6-3 victory on Tuesday, completing the Wimbledon men's quarter-final line-up after their match was suspended overnight in fading light.
They left the contest level when the umpire called time, much to the frustration of 10th seed Berdych, who has suffered a string of delays at the tournament and tried to get the match moved to Centre Court to be finished under the floodlit roof.
A pumped-up Vesely, 22, had the momentum on Monday, snatching a 71 minute fourth set on a tiebreak to force the decider.
But it was 2010 finalist Berdych, 30, who seized the initiative in the fifth, breaking Vesely's first service game.
Berdych will play 22-year-old Frenchman Lucas Pouille, seeded 32, in the last eight.
Kerber battles past Halep into second Wimbledon semi-final
German fourth seed Angelique Kerber outfought Romania's Simona Halep in a last-eight battle of counter-attackers, winning 7-5, 7-6(2) to reach her second Wimbledon semi-final.
In a gloriously unpredictable and at times spectacular match, both players stretched each other's defences with an array of pinpoint topspins, slices and dropshots, but struggled with their serves.
In a first set that featured nine breaks, Halep held hers just once in six attempts, conceding the set on a double fault.
The pattern of the second set was almost as unconventional, with the German, who won her maiden Grand Slam title in Australia in January, failing to serve out the match at 5-4 before coming through a tie-break that she dominated.
Unseeded Vesnina in last four
Russia's Elena Vesnina, the last unseeded singles player standing, reached her first grand slam semi-final on Tuesday, defeating 19th seed Dominika Cibulkova 6-2, 6-2.
Vesnina's power and accuracy on Wimbledon's Court One saw her comfortably ease past the Slovak, who may have had to postpone her wedding on Saturday had she made it through.
Vesnina, ranked 50 in the world in singles, is best known as a doubles specialist and has won two majors with Ekaterina Makarova, her opponent in the previous round.
Vesnina will play world number one and defending champion Serena Williams in Thursday's semi-finals.