By Martyn Herman
LONDON (Reuters) - Sixteen nations will do battle this week to secure the last eight spots for the revamped Fed Cup finals in April with some heavyweights desperate to avoid missing the party.
After the incident-packed launch of the rebranded Davis Cup Finals in Madrid in November, a marathon week for the men featuring 18 nations and culminating in glory for Spain, the ITF's flagship women's team event is taking a similar path.
Gone is the old format whereby two teams would emerge from the World Group to contest a final at the end of the season.
In its place will be a 12-nation week-long event in Budapest in April. With such a quick turnaround the stakes have been raised considerably for the eight qualifying ties.
Holders France and runners-up Australia are exempt from qualifying while the Czech Republic have received a wildcard, as have hosts Hungary. Bidding to join them will be the likes of the United States, Spain, Russia and Romania.
The U.S., out on their won with a record 18 Fed Cup titles, host Latvia with newly-crowned Australian Open champion Sofia Kenin joined by Serena Williams and teenager Coco Gauff.
Kenin, 21, has rocketed up the rankings and will lead the team, having moved ahead of 23-time Grand Slam singles champion Williams who will be the U.S. number two for the tie.
"It's a special feeling to be ahead of her; I'm just super excited -- I can't wait to compete, be on the same team with her in Fed Cup," Kenin said in the build-up to the tie.
Five-time winners Spain take on Japan on outdoor clay in La Manga won all three previous meetings but kowing their task will be tougher this time with world number 10 Naomi Osaka back in team colours after skipping the competition last year.
Last year's semi-finalists Romania host four-time champions Russia in Cluj but will not be able to call on the inspirational fighting spirit of Simona Halep who misses the tie.
Canada's hopes of reaching the Budapest showpiece have been dealt a blow with world number six Bianca Andreescu ruled out of the singles for the clash with Switzerland in Biel.
That means another chance for Leylah Annie Fernandez, 17, who takes the second singles spot behind Eugenie Bouchard.
Fernandez, who made her debut last year against the Czechs, takes on Swiss number two Jil Teichmann in the opener before Bouchard's stern test against world number five Belinda Bencic.
Britain will be without Johanna Konta for their trip to Slovakia, while in other ties the Netherlands host Belarus, Brazil are at home to Germany and Belgium welcome Kazakhstan.
Ties are contested over five rubbers -- four singles and a potential deciding doubles.
(Reporting by Martyn Herman; Editing by Ken Ferris)