Over the weekend Novak Djokovic was participating in the second edition of the Laver Cup, as the in-form player of Team Europe. Not only that, two weeks after his US Open win, Djokovic is now comfortably the best player in the world once again after a gap of a little over two years.

We addressed the then echoing question in this space a few months ago of whether the Serb would ever regain his best form after clearly struggling in the first half of the season. The argument was that given the fact Djokovic’s best was arguably the best that any tennis player has ever played at a specific time, an exact repeat would be unlikely, but he should be challenging majors sooner rather later.

Djokovic has gone one better: he’s now won both Wimbledon and the US Open as the two latter majors of the year and coupled it with the elusive Cincinnati Masters title, which completed his collection of ATP 1000 crowns.

With the US Open, he is now third on the all-time major winners list with 14 Grand Slam titles, tied with Pete Sampras, behind Roger Federer (20) and Rafael Nadal (17). Given that those 14 majors have come in the most competitive era of men’s tennis that further adds to the credentials of Djokovic in the perpetual, even if inconclusive, Greatest Of All Time (GOAT), which has traditionally been dominated by Fedal.

Neither Federer nor Nadal held all four majors at the same time as Djokovic did in 2016. Now the Serb also has all the ATP 1000 that nobody else in the history of sport has. Not to mention his winning head-to-head over both Federer and Nadal.

And so in a couple of months’ time, the question has shifted from whether Djokovic would ever win a major again - something that has been posed against Federer and Nadal in the past as well - to now being just how many he would end up with.

It is fitting that once Federer, Nadal and Djokovic all hang up their racquets, they would be the three most decorated male tennis players of all time. The sequence of greatness will of course always be subjective given the contrasting arguments that each of them puts forward.

But since that moment is quite a few years ago, it’s very much about the here and the now right now, and the reshuffling of the pecking order that the sport is undergoing once again.

After winning the US Open, Djokovic was always the favourite to end the year as the World No 1, but the current top-ranked player Rafael Nadal, could’ve made a fight of it with a strong showing in the remainder of the season. However, after having being forced to pull out of the Asia leg - Beijing and Shanghai - Djokovic is all but certain to be the year-end World No 1.

There are two ATP 1000 tournaments - Shanghai and Paris - remaining in the season, in addition to the World Tour Finals in London. On paper there is a race brewing for the number one ranking that features at least four players.

Nadal currently has 8,760 points, Federer 6,900, Djokovic 6,445, and Juan Martin Del Potro 5980. Mathematically even number 5 ranked Alexander Zverev (4,890) is in the hunt.

Having won Beijing and finished runner-up in Shanghai, Nadal would lose 1,100 points, bringing him to 7,760 points by mid-October. Federer won Shanghai last year so he would need a repeat of that to stay at 6,900. Djokovic, meanwhile, missed the entirety of this part of the season last year so he only has points to gain.

Depending on how Djokovic fares in Shanghai, by the time the ATP Masters 1000 in Paris and the World Tour Finals come - with a collective 2,500 points up for grabs - it could be a straight shootout between Nadal and Djokovic for the World No 1 title given that the Spaniard doesn’t have much to defend from these events from last year.

Alternatively, if Federer defends Shanghai, that shootout could become three-way given that he too does not have much to defend in Paris and London.

A lot of course also depends on whether Nadal returns from injury this season at all. Given his history with injuries - his greatest nemesis - the Spaniard might call it a season and start planning for the Australian Open in January. In that case Djokovic would only have to worry about a late flurry from Del Potro or Zverev, as the only threats to his rankings goals.

Even so, what tennis fans would really love is Djokovic, Nadal and Federer all at it together at the end of the season to make the start of 2019 even more exciting. They would also egg on the likes of Zverev to give the old guard a veritable challenge.

For the time being, however, Djokovic is once again the man to beat. And he is primed to finish the year as the top-ranked player in the world for the first time since 2015.