As the Tours begin to turn from hard courts to clay courts, what have we learned so far this year? Wimbledon.com picks out six things to think about...

1. Are we now living in the Novak Djokovic era?

Djokovic’s toughest battles, it now appears, are with those above him in the record books rather than those below him in the rankings. The Serb has reached that point where every trophy he wins is melted down into numbers, percentages and decimal points and stacked up against the greats of the game. His latest achievement – becoming the first player to complete the Indian Wells-Miami title sweep on three separate occasions – was further proof, if needed, how far ahead he is of the chasing pack. The world No.1 is now more than 4,000 ranking points (the equivalent of two Grand Slam titles) clear of Roger Federer in second place, and this week he took the Swiss’ place in the top five all-time match-win percentage leaders, slotting in behind Rafael Nadal, Bjorn Borg, Jimmy Connors and Ivan Lendl. Next Monday also brings up a significant landmark – Djokovic will spend his 142nd week at the summit of the rankings, surpassing Nadal’s haul of 141 weeks. It appears the man from Belgrade, at 27 years old, is at the peak of his powers.

2. Is the gap between Serena and the rest is increasing?

Serena loves winning and nowhere more so than in Key Biscayne. As the Florida native romped past Carla Suarez Navarro in less than an hour to claim her eighth, yes eighth, Miami Open crown, it begged a question: is the distance between Serena and her would-be challengers bigger than it has ever been? The numbers would suggest yes. Her three longest winning streaks of 34 (2013), 25 (2013/14) and 21 (current run) have been compiled in the past two years. The most telling stat, however? The American, incredibly, has won 24 of her last 25 matches against top 10 opponents. Against the best, she produces her best. And in this era, she is unrivalled. 

3. Murray is in a better place now than he was 12 months ago:

Andy Murray’s last act in Miami may have been to drop a 6-0 set to Djokovic, but heading into the clay-court season there are encouraging signs for the Scot. With consistency seeping back into his game and his back surgery a distant memory, the question now for Murray is belief – belief in his ability, belief in his fitness and most importantly, belief in his game plan against the Big Four, who he is on a 12-match losing streak against. In the Miami final, Murray came out playing the aggressive brand of tennis that lifted him from nearly-man to two-time Grand Slam champion under Ivan Lendl. And for much of the match, it worked. His loss, ultimately, was less about tactics and more about execution. That ability to produce his best tennis on the big points was key to Murray’s breakthrough in 2013, and that skill can only flourish with frequent visits to the latter stages of big tournaments. This, it must be remembered, was his first ATP Masters 1000 final in two years.

4. Nadal’s form

For many years now Rafael Nadal has had questions hanging over his physical well-being. A spate of knee injuries, a problematic back, appendicitis and an unfortunate ankle injury have curtailed his achievements in recent times, but after a third round loss to Fernando Verdasco in Miami the debate surrounded the mental side of his game. The Spaniard said nerves played a role during the North American hard-court swing; nerves he will be hoping to grind through when the European clay-court season gets under way. The worry for Nadal as he heads into the most important part of his season is his lack of competitive match practice deep into tournaments. His losses of late have tended to come early and against lower-ranked opposition, with his last 10 defeats coming against the world No.85, 144, 56, 21, 124, 127, 7, 28, 6 and 34. But if there is one thing Nadal has taught us, it’s to never write him off. Particularly with clay underfoot.

5. Halep is Serena’s closest challenger

With a host of big names struggling of late – Maria Sharapova, Eugenie Bouchard, Caroline Wozniacki, Victoria Azarenka, Agnieszka Radwanska and Petra Kvitova – Simona Halep has emerged as the player most likely to challenge Serena. The Romanian, who lifted the biggest title of her career at Indian Wells, pushed Serena all the way in the Miami semi-final, which was arguably the match of the tournament, men or women. For Halep, the issue is sometimes belief. She raised eyebrows at the Australian Open when she said suggested her run to the quarter-finals “was enough for her”, but if the past month proved anything it’s that semi-finals and finals are where she belongs. “If I want it strong enough, I can reach further and further,” she wrote on Facebook. Maybe that little bit of ruthlessness is all that’s missing.

6. Talented teenagers continue to impress

Despite the absence of Nick Kyrgios, teenagers still dominated the early headlines in Miami. Four of them - Borna Coric, Alexander Zverev, Hyeon Chung and junior world No.1 Andrey Rublev - reached the second round, marking the first time in eight years four teenagers won matches at Crandon park. The last time it happened in 2007, the players’ names were Novak Djokovic, Andy Murray, Sam Querrey, Juan Martin del Potro and Evgeny Korolev. There’s still a long road to negotiate, but there’s something about the new generation of ATP talent that excites. 

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