By Ian Ransom
MELBOURNE (Reuters) - Last year's Australian Open kicked off the biggest shakeup in men's tennis for a decade but Novak Djokovic is primed to stave off the charge of 'Generation Next' and take back his throne at Melbourne Park.
Stan Wawrinka holds the title and a band of young upstarts are determined to topple the 'Big Four', but Djokovic has the fitness and the momentum to reassert himself on the blue courts by the banks of the Yarra River, where he claimed three successive titles from 2011-13 and his first in 2008.
Though upended a year ago by Wawrinka in a cataclysmic quarter-final, a match seen as the beginning of the end for the old guard, Djokovic finished the year with victory at the World Tour Finals, the top ranking and the respect of his greatest rivals.
"The only guy who was really consistent was Novak," Roger Federer said at the Brisbane International last week.
"He was still there when it mattered the most."
Adding to Djokovic's chances are a kind draw and fitness doubts over his biggest threats.
With Federer, Andy Murray and Rafa Nadal bunched on the other side of the draw, only one could meet the Wimbledon champion in the final.
Barring his record ninth French Open trophy, Nadal had a tough 2014.
Having lost to Wawrinka in the Melbourne Park final when battling a back injury, the second half of his year was wiped out by a wrist problem and appendicitis.
The Spaniard's new campaign got off to a miserable start at the Qatar Open last week where he was dumped from the first round by German journeyman Michael Berrer.
Sixth seed Murray, though recovered from back surgery in 2013, struggled to find his best tennis last year and has had a major shakeup in his entourage, parting ways with assistant coach Dani Vallverdu and fitness trainer Jez Green in November.
Federer may be the best placed to stop Djokovic and the Swiss master's 1,000th career win, reached by beating Milos Raonic in the Brisbane International final, proved he still has the hunger to challenge at the age of 33.
Federer's last grand slam triumph was at Wimbledon in 2012, however, and his ability to win seven matches of best-of-five-set tennis remains the biggest question mark.
Wawrinka's quarter-final upset of Djokovic in a five-set thriller was arguably the match of the tournament last year, and avenged his defeat in another marathon against the Serb at Melbourne Park in 2013.
Though the 29-year-old Swiss failed to reach his Australian heights at the other three grand slams, the fourth seed is peaking at the right time.
Sharing in a morale-boosting Davis Cup win with Federer at the end of the year, Wawrinka also won at Chennai in the leadup and is on collision course for a mouth-watering semi-final against Djokovic.
To get there he may need to overcome Japanese trailblazer Kei Nishikori, who became the first man from an Asian country to contest a grand slam singles final at the U.S. Open.
Like 10th seed Grigor Dimitrov and eighth seed Raonic, the clean-hitting Nishikori, who stunned Djokovic in the Flushing Meadows semi-finals, is considered among the brightest hopes to rock the establishment.
(Editing by Peter Rutherford)