Klitschko and his brother Vitali, also a former world heavyweight champion and now the mayor of Kyiv, have both taken up arms against invading Russian forces.
The 14-time Grand Slam winner said he is happy and proud to have reached the summit of the game for a fourth separate spell.
Summary of sports events and persons who made news on Saturday
India's singles challengers at the Chennai Open on Saturday drew tough first round opponents as Yuki Bhambri was pitted against world number 56 Dutch Robin Haase while comeback man Somdev Devvarman will open his campaign against Czech Jann Hajek.
World number one Novak Djokovic turned the page on his contentious US Open exit and began his claycourt season with a convincing 6-3, 6-2 victory over wildcard Salvatore Caruso in the second round of the Italian Open.
'Goran had quite a big influence on me to change my mentality and focus on my game. He changed my serve, I started to get aggressive and that is what I needed in my career'
A summary of sports events and sports persons, who made news on Thursday
Djokovic may never feel the affections of the crowd savoured by Federer and Spaniard Rafael Nadal but his record of 16 Grand Slam titles is proof that tennis is no popularity contest.
Former world number two Tommy Haas officially announced his retirement from tennis at the BNP Paribas Open in Indian Wells on Thursday, ending a career that spanned more than two decades.
Two-time champion Marin Cilic of Croatia kept his hopes alive, coming from behind to beat Sergiy Stakhovsky of Ukraine 4-6, 6-2, 6-2 and make the quarter-finals of the Aircel Chennai Open ATP tennis tournament, in Chennai, on Thursday.
A summary of sports events and persons who made news on Tuesday
Sania Mirza and her Czech partner Barbora Strycova stormed into the quarter-finals of the BNP Paribas Open 2017 tennis tournament with a straight-set win over their opponents in the women's doubles at Indian Wells.
The fast rising Indian pair of Divij Sharan and Purav Raja clinched its first ever ATP tour level title with a hard-fought win over Edouard Roger-Vasselin and Igor Sijsling in the summit clash of the Claro Open, in Bogota.
Big-serving Canadian Milos Raonic fired 19 aces to topple Sam Querrey 6-4, 6-4 and set up a second-round clash with either Dan Evans or Russian 10th seed Andrey Rublev.
While tennis is a lucrative sport for those at the top -- the 2020 Australian Open singles champions each took home A$4.12 million ($2.52 million) -- those in the lower echelons often struggle to make ends meet.
Third seed N Sriram Balaji overcame early jitters to quell a spirited challenge from compatriot Ramkumar Ramanathan in his opening match at the CCI-ITF men's US $15,000 tournament 2012, at the CCI courts, in Mumbai, on Monday. The Chennai-based lad won 7-5, 6-4 in an hour and 50 minutes.
The 'Big Three' of tennis world -- Roger Federer, Rafael Nadal and Novak Djokovic -- won't lose much due to the suspension of professional tours since they have already created their own legacies but the real struggle is for lower-ranked players, including the Indians, says legendary Vijay Amritraj. Amritraj said the trio of Federer, Djokovic and Nadal, who have a tight grip over Grand Slam tournaments, won't feel any financial stress or the pressure of progress.
Australia's Alex de Minaur fought back from a set down to beat former world number one Andy Murray
But for the first time, that golden trio will be having an anxious glance over their shoulders. The past week in London has revealed a new fearlessness in the generation of 20 somethings expected to fill the void when they call it a day.
On the men's side, the fields have already been divided into two ATP 250 tournaments.
Spaniard Nadal was in all sorts of trouble, trailing by a set and 5-4 and with 69th-ranked Rosol serving at 30-0, but his Czech opponent framed a basic backhand volley at 30-15 and blew his chance, Nadal going on to win 1-6, 7-5, 7-6(4).
Sania, the country's finest woman doubles player, who began the year with the number one ranking, closed it at number 9.
Rohan Bopanna Aisam-ul-Haq Qureshi won their first ever ATP Masters tournament after whipping away the challenge of Julien Benneteau and Nicolas Mahut in straight sets in the final, in Paris, on Sunday.
Roger Federer took a big step towards securing his endangered place in the ATP World Tour Finals by overcoming rising Canadian talent Vasek Pospisil 6-3, 6-7(3), 7-5 in the Basel Open semi-finals on Saturday.
India number one Somdev Devvarman registered the biggest win of his career, beating world No 5 Juan Martin Del Potro in the first round of the Dubai Duty Free Championships, on Tuesday. The victory, though, was achieved after the Argentine retired mid-way through the contest.
The only Indian survivors in the Delhi Challenger will face off for a quarter-final place on Wednesday.
The Indo-Pakistan duo will take on third seeds Jarkko Nieminen of Finland and Robert Lindstedt in the championship round.
India ended its campaign at the Fed Cup with a fourth place finish after losing the classification tie 1-2 to Korea as the team badly missed injured Karman Kaur Thandi, who did not play on Saturday, in Astana, Kazakhstan.
The absence of Japan's Kei Nishikori from this year's Australian Open has turned the spotlight on Chung Hyeon as Asia waits for its first men's Grand Slam singles champion.
Ash Barty's bid to end the host nation's long wait for a homegrown Australian Open champion will begin against Ukraine's Lesia Tsurenko
Halep sustained the injury last month while training for the Wuhan Open, where she lost in the second round. She then retired midway through her opener in Shanghai.
Summary of sports events and persons who made news on Thursday
'If it is a World Cup then yes, doing away with home and away format, is okay'
Zverev has not lost to Wawrinka in two previous meetings but is not taking the 2014 Melbourne Park champion lightly.
After stunning top seed Karan Rastogi on Thursday, sixth seed Yuki Bhambri turned giant-killer, scalping No 4 Gero Kretschmer of Germany in straight sets, to storm into the final of the CCI-ITF US$15,000 Men's Futures tennis tournament at the Cricket Club of India in Mumbai on Friday.
IMAGES from Day 1 of the Wimbledon Championships played on Monday.
Australian Open tournament director Craig Tiley has defended giving Roger Federer 'prime time' treatment at the year's first Grand Slam, saying it was a matter of meeting fans and broadcasters' demands for the 'box office' athlete.
Leander Paes and Radek Stepanek downed Jonathan Erlich and Richard Gasquet in straight sets to reach the quarter-finals of the ATP Indian Wells Masters tournament.
Somdev Devvarman failed to make the singles main draw of the Toronto ATP Masters after going down fighting to third seed Denis Istomin of Uzbekistan in the second round of the qualifying event. The 14th seed Indian began well but lost 6-4, 3-6, 6-7(10) to the world number 54 Uzbek in the second and final round.
'Everyone thinks it was a money-related issue, but it wasn't'
