Favourites Russia sealed a crucial win over hosts Poland on Wednesday's opening day of the Fed Cup by BNP Paribas Europe/Africa Group I event in Zielona Gora.
Anastasia Pavlyuchenkova and Natalia Vikhlyantseva were each too strong for respective opponents Magda Linette and Iga Swiatek and look to have cleared Russia's path to Saturday's decisive tie where a win will earn them the right to play off for a place in World Group II next year.
Victory over Denmark, who are not expected to pose formidable opposition on Thursday, will confirm Russia's place atop Pool A, which comprises three teams.
Who they would face in Saturday's decider is completely open to question, after Sweden beat Ukraine and Bulgaria overcame Estonia in Pool B in early action on Wednesday.
Pavlyuchenkova, the world No. 32, was preferred for the No. 1 rubber ahead of Daria Kasatkina, who is currently ranked at 14, and she didn't disappoint, proving too strong for Magda Linette, Poland's top player ranked at 89.
A powerful baseline duel saw the Russian win 64 63 in 90 minutes. She forced errors from her opponent and did just enough to hold Linette at bay.
Pavlyuchenkova broke Linette's serve twice in the first set and lost her serve only when she relaxed a little with the end of the set in sight.
Linette took a medical timeout in the second set but it made no difference, as the strong Russian broke twice more to secure the win and leave the home fans, who turned out to watch the attractive encounter at the Hala Widowiskowo-Sportowa, disappointed.
In the opening rubber, Vikhlyantseva demolished Swiatek 60 62 in 53 minutes. The Pole did all she could but was no match for the hard hitting Russian who forced her opponent into countless errors.
Poland gave the few hundred home fans who stayed on good reason to cheer as Alicja Rosolska and Swiatek scored a thrilling 60 36 63 doubles victory over Kasatkina and Margarita Gasparyan. Rosolska, in particular, showed her doubles skills with some excellent volleys and smashes, and a few excellent poaches at the net.
Russian captain Igor Andreev said his choice to play Pavlyuchenkova instead of Kasantkina in the singles was because he believed the court conditions and freshness favoured the former.
"Daria arrived on Monday night and Natasha was here a day before and had more time to practice, the court also perfectly suits her game, that was one of the reasons and (the result shows) that I made the right choice," Andreev said.
In the early tie at the main arena, Bulgaria's balanced, experienced side overcame Estonia 2-1. The Baltic team had pinned their hopes mainly on world No. 20 Anett Kontaveit but it was their opponents from the Balkans who prevailed by winning the decisive doubles after they shared the spoils in the singles rubbers.
The Bulgarian duo of Viktoriya Tomova and Isabella Shinikova were always in command against Kontaveit and Maileen Nuudi, winning 62 62. They put on a solid performance and perfectly executed a few deft attacking lobs that were a joyful sight for the spectators.
Shinikova, playing as Bulgaria's No. 2, showed her experience and put her team on the scoreboard in the opening rubber with a 76(6) 63 win over Valeria Gorlats.
The first set was a litany of broken service games and missed chances, but Shinikova got across the line after a long tie break. Once that was secured, the 28-year-old took control and surged ahead to win comfortably.
Kontaveit was pushed hard by Tomova in the battle of the two No. 1 players. The Bulgarian overcame the disappointment of easily losing the first set 61 and battled hard in the second, forcing errors from the world No. 20 in many, lengthy baseline exchanges. She levelled the rubber by winning the tie break 7-4 but that defiant effort evidently emptied Tomova's tank, and Kontaveit regained her dominance in the deciding set as she won the first five games on her way to a 61 victory.
Sweden emerged victorious in their tie against Ukraine at Zielona Gora's secondary venue, and also did so by winning the doubles.
Ukraine's Dayana Yastremska dismissed Johanna Larsson 64 62 in the opener in 72 minutes, before Rebecca Peterson made easy work of Lesia Tsurenko 60 62 in just 53 minutes.
The doubles was a much longer affair and Larsson and Peterson needed two hours and 18 minutes to see off Nadia Kichenok and Marta Kostyuk 26 63 75.
Thursday's action sees Russia play Denmark in Pool A, while in Pool B, Sweden meet Estonia and Bulgaria face Ukraine.