Russia, Italy and defending champions Czech Republic, with 14 Fed Cup titles between them, take their powerful legacies into the semi-finals this weekend.
But many eyes will be turned away from the all-European last-four ties to focus on the play-off between the United States and Sweden in Florida where Serena and Venus Williams will be playing together for only the second time in six years.
The semi-finals see the Czech Republic, the two-time defending champions, travel to Palermo to face Italy, the winners in 2006, 2009 and 2010.
Francesca Schiavone and Flavia Pennetta return to the Italian squad after missing the 3-2 first round win over USA.
But world number seven Sara Errani and Roberta Vinci, the 12th-ranked player, are expected to shoulder the burden on Saturday and Sunday.
Vinci also holds the record (18-0) for the most Fed Cup doubles rubbers without defeat.
The defending champions, on a three-year undefeated streak in Fed Cup, are without doubles world number four Andrea Hlavackova, who has been replaced by singles number 20 Klara Zakopalova.
That leaves Lucie Hradecka as their lone doubles specialist.
Former Wimbledon champion Petra Kvitova has won 13 of her last 14 Fed Cup singles rubbers.
Twelve months ago, the Czechs trounced Italy 4-1 in the semi-finals.
"Against the Czech Republic, it will be tough for sure," said Vinci.
"Last time we lost in the Czech Republic 4-1, but the court was quick and this time we play on a clay court in Italy. I hope the outcome will be different."
In Moscow, four-time champions Russia, again without Maria Sharapova, tackle the Slovak Republic who took the title in 2002.
In the absence of Sharapova, Russia will pin their singles hopes on Maria Kirilenko.
For the Slovaks, Daniela Hantuchova, who played in her team's 2001 loss to the Russians, is still going strong with her 30th birthday just around the corner.
At Delray Beach in Florida, the USA will field world number one Serena and sister Venus in the same Fed Cup team for only the second time since 2007.
For their World Group play-off against Sweden, the home side will also boast number 16 Sloane Stephens and Varvara Lepchenko, the world 27.
Serena has lost just one set in 11 appearances for her country.
"In general I feel a little bit of pressure when I'm playing for the team because I want to be able to do really well," the 15-time Grand Slam champion told www.fedcup.com.
"You're not just playing for yourself. You don't want to let your friends and your team down"
This weekend's clash is just the fifth World Group play-off 17-time champions USA has ever had to contest.
Fed Cup fixtures on Saturday and Sunday:
Italy v Czech Republic
Russia v Slovakia
World Group One play-offs
Germany v Serbia
Switzerland v Australia
Spain v Japan
At Delray Beach
USA v Sweden
World Group Two play-offs
Belgium v Poland
France v Kazakhstan
At Buenos Aires
Argentina v Great Britain
Ukraine v Canada