LONDON, Great Britain -- Johanna Konta and Katie Boulter emerged victorious in three-set tussles on Sunday, allowing Great Britain to claim their Fed Cup World Group II play-off tie over Kazakhstan and put the Brits into World Group II for next year.

British No.1 Konta came back from a 4-1 deficit in the final set to squeak past Yulia Putintseva, 4-6, 6-2, 7-5 in two hours and 21 minutes and put her squad up by two matches to one. World No.46 Konta extended her winning streak in Fed Cup singles matches to 11 straight after Sunday's win.

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Boulter was set up to close out the tie, and after dropping the first set in a tiebreak, the World No.86 claimed a comeback win, defeating Zarina Diyas, 6-7(1), 6-4, 6-1, and sending the British team safely into World Group II.

Great Britain was contesting its fifth World Group II play-off tie since 2012, and it had lost away ties at this stage to Sweden in 2012, Argentina in 2013, Romania in 2017, and Japan last year. This time, it was the Brits who prevailed, preventing Kazakhstan from making their World Group II debut.

A raucous crowd supported Putintseva as well as Konta as the two top players from their respective nations squared off in Sunday's first match. It was Putintseva who notched the one-set lead after breaking Konta at 4-4, then serving out the opening frame at love. But Konta surged back to take the second set in 35 minutes, dropping just two points on serve in that set.

However, Putintseva, who staged a remarkable comeback in her win over Boulter on Saturday, used her dazzling speed and venerated grit to break Konta twice in the first five games of the decider. Nevertheless, Konta pulled both breaks back to get level by 5-5. Konta finally broke Putintseva at love to obtain the victory, clawing back in a final set that took over an hour to complete.

The stage was set for a stirring clinching rubber by up-and-coming 22-year-old Boulter, but Diyas, a long-time WTA veteran who is still only 25 years old, had other ideas. Diyas came back from a break down at 4-3 in the opening stanza to queue up a tiebreak, and the experienced Kazakh zoomed through the breaker to pick up the 51-minute first set.

Boulter was perilously close to losing the match in straight sets, as Diyas stayed with the Brit through 4-4 in the second. But after holding for 5-4, Boulter grasped an opportunity on the Diyas serve in the following game, claiming two set points. Diyas faltered on the second, firing a double fault to align the match at one set apiece.

The first four games of the decider were protracted, but Boulter was able to come out of that section with two service holds and one break of Diyas to lead 3-1. After that, Boulter won six straight points to ease to 5-1. Serving for the match, Boulter faced a break point after reaching her first match point, but she extricated herself from that situation, completing her victory on her third chance.

Elsewhere in the World Group II play-offs, Russia, Slovakia, and Japan moved into World Group II for next year after each nation attained insurmountable 3-0 leads on Sunday.

Anastasia Pavlyuchenkova claimed her second consecutive straight-set win of the weekend, defeating Martina Trevisan, 6-4, 6-3, to polish off Russia's win over Italy. Russia is a four-time Fed Cup champion, winning the title in 2004, 2005, 2007 and 2008, and they have reached the final on a further seven occasions, most recently in a 3-2 defeat to Czech Republic in the 2015 final.

Dominika Cibulkova also closed out Slovakia's tie over Brazil with her second straight two-set win, easing past Beatriz Haddad Maia, 7-6(3), 6-0 on Sunday. Slovakia therefore keeps their streak alive of having competed at World Group or World Group II level since 2007.

Japan also hit the magic number after Misaki Doi beat Bibiane Schoofs, 6-3, 6-2, to win their tie against the Netherlands. Japan's best finish at a Fed Cup is the final four in 1996.