Novak Djokovic ended the year in similar fashion to how he began it: he hoisted one of the most coveted trophies in tennis at the 2013 ATP World Tour Finals to signal the end of an unforgettable season.
Fortunately, the 2014 Australian Open is only two months away.
Here we'll highlight the biggest takeaways from the 2013 year-end championship and what the results in London could mean for men's tennis moving forward.
Rafael Nadal vs. Novak Djokovic Will Forever Be Must-See Television
Although Novak Djokovic earned a convincing straight-sets win over Rafael Nadal in Monday's championship match, you'd be hard-pressed to find someone who wasn't on the edge of their seat while watching it unfold.
The two superstars met six times in 2013. Fittingly, the seasons closes with Djokovic evening up their head-to-head series at 3-3.
While Nadal has seized the No. 1 world ranking heading into 2014, Djokovic sent a clear message with his impressive victory in London. By beating Rafa en route to his second consecutive year-end title, Djokovic has reaffirmed his status as the man to beat heading into the Australian Open.
There isn't a better returner in tennis, and it's almost impossible to argue that there's a better hard-court player in today's game.
With both Nadal and Djokovic in the midst of their physical primes and playing their best tennis at the same time, 2014 promises to produce plenty of fireworks, as each looks to maintain an edge over the other.
Next Year Could Be Roger Federer's Last
2013 marked the first year since 2002 that Roger Federer failed to reach a Grand Slam final. This past season also saw the 17-time major champion fall to No. 7 in the world for the first time in a decade and win just one singles title all year.
Federer's quiet exit in the World Tour Finals semis served as a microcosm of his season.
The Swiss legend fared decently against lesser opponents for the most part but struggled against the sport's elite, posting a losing record against the top 10 (4-10) and failing to win a single match against the other three members of tennis' Big Four.
Federer's losses to Nadal and Djokovic in London suggest that his days of contending with the other three recent Slam champions are over. While Federer is always dangerous on fast-playing surfaces where the conditions are conducive to his game, he's become inconsistent at events he used to dominate, including the ATP World Tour Finals.
At age 32, it appears that Federer will have to throw rankings out the window and be content to play for his legacy moving forward.
Juan Martin del Potro is Ready to Crash the Big Four's Party
Juan Martin del Potro will be disappointed not to advance from the group stage at the World Tour Finals this November, but overall, he's got to be pleased with his performance in 2013.
Delpo showed glimpses of greatness during round-robin play in London that lead many to believe he's ready to challenge the likes of Nadal, Djokovic and Murray in 2014. Remember, the 6'6" Argentine is one of the few players in today's game to have won a Grand Slam. Plus, he just turned 25 this past September.
Having won eight singles titles since the start of 2012 and reaching his first Grand Slam semifinal in four years at Wimbledon this past summer, Delpo is ready to earn some signature victories next year that should propel him even higher in the ATP rankings.
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