Keothavong has had an impressive start to the new season
British number one Anne Keothavong is one win away from her first WTA Tour final after beating Ajumi Morita in the last eight of the ASB Classic.
Keothavong, the world number 60, won the first set 6-0 in just 22 minutes in Auckland before her Japanese opponent retired with a hamstring injury.
The win puts Keothavong in the semi-finals of a WTA Tour event for only the second time in her career.
The 25-year-old will take on Elena Vesnina of Russia.
Vesnina recorded a 6-3 0-6 6-3 over Denmark's Caroline Wozniacki.
"It's a shame Ayumi had to retire but I thought I started better today than in my previous matches and was hitting the ball pretty sweet anyway," Keothavong told her website.
"She's played a lot of tennis in the last few days and she was bound to be a little tired but I'm through to the semis and that's what matters for me.
"It's not a bad start for the first tournament of the year and I'm looking forward to tomorrow's match whoever I play.
"I've got nothing to lose and will go out there with the same focus I had today and give it my best shot."
Keothavong's previous semi-final appearance was in Kolkata in 2007.
World number four Elena Dementieva also reached the semi-finals after beating Israel's Shahar Peer 6-3 6-1, who faced protests from around 20 people over her country's military offensive in Gaza.
The protesters wanted Peer to withdraw from the tournament but the 21-year-old said she had been unaffected by the action, adding: "I'm not the government of Israel and I'm not representing Israel as a politician."
Dementieva, who will play unseeded Frenchwoman Aravane Rezai in Friday's semi-finals, said: "I'm sure it was a tough day for her because of the situation in her country."