Two-time Wimbledon champion Petra Kvitova reached her first final since returning from a career-threatening hand injury after Lucie Safarova retired from their match in Birmingham.
Kvitova, 27, was leading 6-1 1-0 in the Aegon Classic semi-final when her fellow Czech quit with a leg injury.
Kvitova is playing in only her second tournament since she was stabbed by an intruder at her home in December.
“I’m enjoying playing again,” said the former world number two.
“I couldn’t play for five or six months and I missed it.
“It wasn’t my choice to have a break but I always try to see positive things. I’m trying to enjoy tennis more and seeing things from a different angle.”
Kvitova looked close to her best against Fed Cup team-mate and close friend Safarova, who was carrying the injury into the match.
Kvitova made an impressive start, dropping just one point as she raced into a 3-0 lead, breaking serve again in the next game before Safarova held at the third attempt for 5-1.
Safarova, a former Wimbledon semi-finalist and 2015 French Open finalist, provided some resistance as Kvitova needed a fourth set point to serve out for the opener.
But Kvitova broke again in the opening game of the second set, before Safarova decided she could not continue.
The seventh seed will play either 2016 French Open champion Garbine Muguruza or Australia’s Ashleigh Barty in Sunday’s final.