Petra Kvitova left fellow Czech left-hander Lucie Safarova staring at possible elimination from the WTA Finals when she beat her 7-5, 7-5 on Wednesday.
Two-time Wimbledon champion and world number five Kvitova, 25, has now dominated her friend and Fed Cup partner 8-0 on hardcourts, grass and clay.
“I’m really glad that I was able to play and win the kind of match after my loss in the first match here,” said Kvitova, who fell to Germany’s Angelique Kerber in straight sets on Monday.
Safarova is now relying on Garbine Muguruza beating Kerber in a White Group match later Wednesday in order to stay alive in the eight-player season finale.
The world number nine looked set to force a decider after racing to a 3-0 lead in the second set, but she squandered her lead with weak serves.
“For sure it was a difficult match. I know that Lucie wasn’t really healthy weeks ago and I’m just happy that she’s here as well,” Kvitova said.
“It’s great to have two Czechs in the WTA Finals.”
The victory was vital for Kvitova, who would also have been facing potential elimination had she lost her second match in the White Group round robin.
The two women said they looked forward to playing together when they face Russia in the Fed Cup final in Prague from November 14-15.
Kvitova and Safarova have led the Czech Republic to three trophies from the last four Fed Cup editions.
“We actually are good friends from the Fed Cup, so I’m really glad the Fed Cup is coming soon and we going to be colleagues and not opponents,” Kvitova said.
Safarova agreed: “I prefer playing with Petra. We always had a lot of fun through Fed Cup weeks. We are a great team, which we show with our results in last few years.”
Maria Sharapova will lead the Russian line-up that includes Ekaterina Makarova, Anastasia Pavlyuchenkova and Elena Vesnina.
The two nations have met five times before in the Fed Cup but three of those meetings were between Czechoslovakia and the Soviet Union.
The Czech team lead their head-to-head record with Russia 3-2, including a victory in the most recent encounter in the 2011 final in Moscow.