Great Britain and Japan are level at 1-1 after day one of their Fed Cup promotion play-off in Miki.
Britain's Heather Watson lost the opening rubber to the in-form Naomi Osaka but Johanna Konta levelled matters when she got the better of Kurumi Nara.
The tie is best-of-five and there will be a doubles contest and the reverse singles on Sunday.
Great Britain are bidding to be promoted to World Group II for the first time since 1993 but they began poorly when Indian Wells champion Osaka secured a comfortable 6-2 6-3 win over Watson.
However, Konta made a good start against Nara, breaking in the opening game, and went on to take the first set 6-4.
It was a similar story in the second set, Konta powering into a 3-0 lead before going on to win it 6-2.
GB team captain Anne Keothavong said: "Jo's just put in a fantastic performance. Her opponent was able to raise her level but Jo was just too good."
Konta will next face Osaka in a potentially high quality showdown on Sunday.
Konta has a 3-0 lead over Osaka in their previous meetings but the Japanese star has won all five of her Fed Cup matches so far.
"I haven't played her in almost exactly a year and I'm looking forward to being on court with her again," said Konta.
"I'm really looking forward to playing against such an in-form player."
Coverage of the ATP Monte Carlo Rolex Masters continues on Saturday with both semi-finals live from 12.20pm on Sky Sports Arena with highlights from 7.40pm.
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