There is still a year to go until a ball is kicked at the 2018 football World Cup in Russia, but the competition's official warm-up event is already upon us.

Over the next 17 days, the holders of FIFA's six continental championships, plus the World Cup holders and the host nation, will compete in international football's tournament of champions, reports Xinhua news agency.

Since its inception in 1997, the Confederations Cup has been won four times by Brazil, twice by France and once by Mexico.

Despite its status as a World Cup dress rehearsal, no previous Confederations Cup holders have gone on to win the World Cup the following year.

Of the previous winners, only Mexico will feature in this year's tournament. Other participants in the 2017 edition are Russia, Germany, Australia, Chile, New Zealand, Portugal and Cameroon.

Xinhua identifies five things to look out for during the June 17-July 2 event, which will be played in Moscow, Saint Petersburg, Kazan and Sochi.

Motivated Ronaldo: Few players will be as motivated to perform well in this tournament as Portugal's veteran talisman Cristiano Ronaldo.

A year after guiding Portugal to victory in the UEFA European Championship, the Real Madrid star will know that another title here will put him on course for a second consecutive Best FIFA men's player of the year award.

That would leave him level with his great rival Lionel Messi with five FIFA player of the year accolades (called the FIFA Ballon d'Or from from 2010 to 2015).

The former Manchester United forward has reinvented himself in recent seasons: his once trademark speed and athleticism being replaced by savvy positioning and clinical finishing.

Despite being just seven months shy of his 33rd birthday, Ronaldo is not far off the best form of his career.

Last month he led Real Madrid to their third UEFA Champions League title in four years, capping off a season in which he scored 42 goals in 46 matches across all competitions for the Spanish giants.

Improved Russia: The tournament's host nation looked to be in freefall late last year when they suffered friendly defeats to Costa Rica and Qatar. Just months earlier they were bundled out of Euro 2016 in the group stage without winning a match.

But a silver lining has appeared on the horizon with a 3-0 victory over Hungary and a 1-1 draw with Copa America champions Chile earlier this month.

Stanislav Cherchesov's team will be without striker Artem Dzyuba, playmaker Alan Dzagoev and midfielder Roman Zobnin here due to injury.

But in emerging talents such as midfield pair Aleksandr Golovin and Aleksei Miranchuk, who are both 21, Cherchesov has good reason to believe his team can cover those losses.

Russia will be further boosted by the country's fervent fans, who are likely to make their match venues a cauldron of noise for opposing teams.

Down-under spirit: While the declaration by Australia coach Ange Postecoglou that he is aiming to "win the tournament, mate" might seem overzealous, they should not be taken lightly.

Australia are unbeaten in their past eight World Cup qualifiers and showed by winning the Asian Cup final in 2015 that they can perform on the biggest of stages.

Their squad includes talented Celtic midfielder Tom Rogic, Hertha Berlin forward Mathew Leckie and Manchester City's Aaron Mooy, who helped Huddersfield Town earn promotion to the Premier League during a loan spell last season.

Thirty-seven years old former Everton attacking midfielder Tim Cahill is also a part of the Socceroos squad and will be keen to preserve his fine record in major tournaments.

Likewise, Australia's trans-Tasman rivals New Zealand should not be discounted as easy beats. The Oceania champions drew 1-1 with the United States in Washington last October, and their squad includes players of the ilk of West Ham defender Winston Reid and Leeds United striker Chris Wood.

Draxler on the rise: Having chosen an under-strength squad, Germany coach Joachim Low is using the tournament as a litmus test for several players ahead of the World Cup.

Among those who will be watched closely is Paris Saint-Germain (PSG) winger Julian Draxler, who has been named Germany's captain for the tournament.

A bit-part player for Germany at the 2014 World Cup, Draxler has become a regular in Low's starting line-up and he can confirm his name in the coach's World Cup plans if he lives up to expectations here. 

Other players that Low will be observing closely include Timo Werner, Emre Can, Joshua Kimmich and Shkodran Mustafi.

Hot Chile: Chile will be aiming for their third major tournament trophy in as many years, having won the Copa America in 2015 and 2016.

Juan Antonio Pizzi's team boasts what is arguably the tournament's most impressive squad on paper. Arsenal forward Alexis Sanchez will again lead his team's attack while Bayern Munich's Arturo Vidal will pull the team's strings in midfield alongside Pablo Hernandez (Celta Vigo) and Charles Aranguiz (Bayer Leverkusen). In goal will be Manchester City's Claudio Bravo.

After a slow start to their 2018 World Cup qualifying campaign, Chile have climbed to the fourth spot in the South American zone standings, within the automatic qualification places.