Play underway on Day 8 at Wimbledon
Kerber has yet to drop a set this tournament and is coming off a match in which she lost just four games total.
But Kerber dominated the tiebreak, going to match point when Halep was bamboozled by a net cord and then taking victory off a backhand error.
The former world No. 1 has won all eight previous semi-finals at Wimbledon, including the 2000 decider when she defeated 18-year-old Serena en route to her first Wimbledon crown.
“I am enjoying it every day here, I’m so happy to be in the semis”, the 28-year-old said.
Her opponent, two-time major champion Svetlana Kuznetsova, sent a shot flying past Williams to go up a break at 5-4 in the opening set.
“I think we both played a really good match on a really high level and we are both really good return players”, said the current world number four after the match.
Play on some of the outside courts has been suspended, however, with Venus Williams leading 4-2 in a first-set tiebreaker against Carla Suarez Navarro.
Nishikori gritted his teeth ahead of the second set and broke back to even the set after dropping his first service game.
Romanian fifth seed Simona Halep recovered to beat a distressed and cramping Madison Keys 6-7(5) 6-4 6-3 and reach the Wimbledon quarter-finals for the second time in her career on Monday. Pavlyuchenkova reached her first Wimbledon quarterfinals – and first at any Grand Slam tournament since 2011 – by eliminating CoCo Vandeweghe 6-3, 6-3. I think I am playing my best tennis.
It was the first match between the two lefthanders since January’s Australian Open, where Kerber saved a match point before beating Doi in three sets in the first round.
Germany’s Angelique Kerber outslugged Romania’s Simona Halep in a quarter-final of the counter-punchers at Wimbledon on Tuesday, shading a compelling two-set match that featured 13 breaks of serve.
“Also, I was not handling it so well off court”, she said.
Nishikori next meets ninth seed Cilic who beat him in the 2014 US Open final.
It will be Kerber’s second appearance in the Wimbledon semi-finals after defeat by Agnieszka Radwanska in the last four in 2012.
The time to call it quits came Monday in the fourth round at Wimbledon, trailing 6-1, 5-1 against Marin Cilic on No. 2 Court.
Cibulkova has the form, confidence and all-round game to win this, but she’ll have to be focused to avoid a slip-up after so many impressive wins.