Novak Djokovic and Nick Kyrgios hope the Davis Cup heals the wounds of their painful Australian Open exits this weekend when they will be the only two men in the top 15 taking part.

World number one Andy Murray has opted out of Britain's trans-Atlantic trip to Ottawa where Canada will be without fourth-ranked Milos Raonic for the World Group opener.

Meanwhile, Australian Open champion Roger Federer and world number three Stan Wawrinka miss Switzerland's tie in the United States.

Rafael Nadal, the runner-up to Federer in Melbourne, will sit out Spain's match in Croatia, who will be missing Marin Cilic, while Japan and France meet in Tokyo with Kei Nishikori, Gael Monfils and Jo-Wilfried Tsonga on the sidelines.

Tomas Berdych is out of the Czech Republic team to face Australia in Melbourne while David Goffin skips Belgium's short hop to Germany.

Just as worryingly for the 117-year-old tournament is Juan Martin del Potro sitting out defending champions Argentina's home tie against Italy.

Despite seeing all of his Grand Slam rivals take a breather, world number two Djokovic -- stunned in the second round in Melbourne by unheralded Denis Istomin for his earliest exit at a major in nine years -- is relishing leading 2010 champions Serbia against Russia in Nis.

"I am overjoyed to be back amongst these guys as we are all close friends and it's a very special atmosphere every time we get together," 29-year-old Djokovic told daviscup.com.

"But Russia are a young team and we can't underestimate them."

Russia, who won the last of their two titles in 2006, will be led by world number 52 Karen Khachnov.

A win for Serbia will set-up a quarter-final against either five-time winners Spain or 2005 champions Croatia who meet in Osijek.

In the absence of Nadal, Spain will be led by 16th-ranked Roberto Bautista Agut and Pablo Carreno Busta, the world 26.

Croatia, however, have to rely on Franko Skugor and Nikola Mektic, ranked at 223 and 319 respectively, neither of whom have ever won a Davis Cup singles tie.

Reputation to repair

At Kooyong in Melbourne, number 15 Kyrgios will try to restore his battered reputation after being accused of tanking in his five-set, second round loss to Andreas Seppi at the Australian Open.

Australia, the 28-time champions, face a Czech side led by world number 54 Jiri Vesely in the absence of world number 12 Berdych.

"I've got to improve a lot of things in my game, I've got to work harder," said 21-year-old Kyrgios.

For Great Britain, Murray dropped out the Canada tie after his shock fourth-round defeat to Mischa Zverev at the Australian Open. World number three Raonic is missing after injuring his groin in his quarter-final loss to Nadal.

With top 50 players Dan Evans and Kyle Edmund, Britain will be favourites as Canada's top singles player is Peter Polanksy, ranked at 128.

The winners of that tie will face either Japan or nine-time champions France in the quarter-finals.

Japan are missing fifth-ranked Nishikori, who was bothered by a hip injury in his defeat to Federer in Australia.

In his absence, Yoshihito Nishioka, ranked 85, leads the Japanese challenge against a French squad who can still boast Richard Gasquet and Gilles Simon, both inside the top 25.

Without Federer and Wawrinka, Switzerland will look to Henri Laaksonen and 35-year-old Marco Chiudinelli, both outside the top 100, to shock their American hosts led by Jack Sock, John Isner and Sam Querrey, all in the top 30.

Top seeds Argentina are without Del Potro and Federico Delbonis, the men who won the reverse singles to beat Croatia in the 2016 final, when they start their title defence on clay in Buenos Aires against Italy.

The winners will face either Germany or Belgium who meet in Frankfurt.