First of all, lets get down to business - this ishow Murray could knock Djokovic off the top spot.

Murray will become number one this week at the Paris Masters if one of these two things occur - Murray wins the tournament and Djokovic fails to reach the final, or, Murray reaches the final and Djokovic falls short of the semi-finals.

Easy, yes? I wouldn't be so sure - Djokovic is not someone who will just hand over his top spot, Murray will have to be on top form to fight him all the way.

Only minutes ago, Murray beat Frenchman Lucas Pouille, attempting to book his place in the quarter-finals of the Paris Masters.

The Scot took the first set 6-3 and then raced into a 4-0 lead in the second, before securing the second set 6-0 to claim victory in just 72 minutes. Murray will now face either Tomas Berdych or Gilles Simon in the quarter-final.

The Serb beatGrigorDimitrov earlier today in three sets to reach the quarter-finals in Paris, he will now face Marin Cilic tomorrow in what could be a thrilling match, between two quality tennis players. Djokovic had to come back from one-set down to beat Dimitrov in three sets.

It could end up being a Murray v Djokovicshowdown in London; however, if Djokovic wins in Paris and Murray fails to make the semi-finals, the Serb would retain his end-of-year ranking for a third consecutive year.

The Serb has spent an impressive 122 consecutive weeks as the world number one, which is the longest amount of time since the Roger Federer remained at number one for a tremendous237 weeks on the bounce between 2004 and 2008.

How has Murray got himself into number one contention?

Djokovic has finished four of the past five years as the world number one, but the Serb has suffered a massivedip in form since clinching the French Open title in May, suffering an early exit at Wimbledon this year.

The 29-year-old, suffered another shock exit this summer, this time at the Rio Olympics, before being stunned by Stan Wawrinka at the US Open, and he has struggled to get back to his high-flying form ever since.

In contrast, Murray has been on fire in 2016, from clinching his second Wimbledon title - to becoming a double Olympic champion at Rio.

Along with reaching the Australian and French Open finals.

The Britis on now track to become the oldest first-time number one since 30-year-old Australian John Newcombe who achieved this back in 1974.