In January, after Novak Djokovic defeated Andy Murray in the final of Qatar Open, it looked like the two, who had dominated proceedings in 2016, would continue the battle for supremacy in the new season.

However, within weeks, the said notion was proved wrong by Roger Federer and Rafael Nadal, who missed most part of the second half of last season with injuries, as they stunned the rest of the pack to reach the final of Australian Open. In what will go down as another chapter of their well-followed rivalry, the Swiss veteran piped the Spaniard in a tightly-contested title match, that went to the decider.

Federer proved his Australian Open run was not a flash in the pan as he went on to win his third Sunshine Double to end his early-season campaign on hard court. Nadal was not far away. He rallied to the final in Miami but suffered another defeat to the 35-year-old.

When the action moved to the dirt, Nadal looked impeccable. While Federer skipped the clay season, the Spaniard unleashed his beast mode, winning three titles on the trot -- Monte Carlo, Barcelona, Madrid -- before easing to a historic 10th Roland Garros title.

The return of Federer and Nadal has spiced up tennis rivalry once again and the focus at Wimbledon, starting July 3, is well and truly on the 'Big Four'.

Apart from the two in-form greats, Murray, the defending champion, will be hoping for a change of fortunes. Also, Djokovic, who had a tough start to the season, clinched a confidence-boosting win at Aegon International last week. It also ended his six-month long title drought.

Novak Djokovic
Novak DjokovicCharlie Crowhurst/Getty Images for LTA

Battle Royale at SW19

Putting the competition for the title aside, there is an interesting subplot that deserves our attention -- the four-way battle for the world number one spot, which is currently being held by Murray.

How can Nadal regain the top spot

Well, fifth-ranked Federer is not part of the race as even a title at SW19 will not help his chances, but world number two Nadal is a firm favourite, given his consistency over the last six months.

Rafael Nadal
Can Nadal successfully carry his recent form into Wimbledon?Clive Brunskill/Getty Image

The 15-time Grand Slam winner now trails Murray by 2105 points, but if the Spaniard reaches the final, he is guaranteed a top spot as he has to overcome the holder in a potential semi-final outing. Notably, the Scott will also drop 2000 points as defending champion of the slam.

What is the current scenario of the top four? Here you go.

Player Points
1. Andy Murray 9,390
2. Rafael Nadal 7,285
3. Stanislas Wawrinka 6,175
4. Novak Djokovic 6,055

[Note: Winner of a Slam event gets 2,000 ranking points, runner-up gets 1,200, semi-finalists get 720 each and quarter-finalists earn 360 each]

Murray's chances?

Murray will retain his numero uno position if he manages to reach the final. However, after his first-round exit at the Queen's last month and injury concerns, it remains to be seen if he can make an impact and stay at the top.

Wawrinka-Djokovic final to decide the new world number one?

World number three Stanislas Wawrinka is just defending 45 points after a second-round exit at last year's Wimbledon. The Swiss, who is drawn in the same half as Nadal and Murray, will have to win the title to become world number one for the first time in his career.

By winning the title, he will also make sure his rivals Murray and Nadal, will not reach the final as he will be required to beat them in the quarter-final and semi-final respectively. After the impressive run to the final in Roland Garros, the three-time Grand Slam winner will be geared up to win his maiden Wimbledon title.

Djokovic, on the other hand, has to reach the final and rely on luck as Nadal and Murray have to be stopped before the semi-final. A title match between Wawrinka and the Serb to decide the Wimbledon champion as well as the new world number one. Sounds exciting?