Despite neither player being in action last week, Roger Federer was able to cement his place as world number one ahead of Rafael Nadal after extending his lead over the Spaniard to 600 points in the ATP rankings.

As the Swiss opted to skip the Dubai Duty Free Tennis Championships to spend time with his family, Nadal pulled out of the Mexican Open in Acapulco with the recurrence of a hip problem which hindered him during the Australian Open in January.

While 36-year-old Federer gave up just 45 ranking points, his great rival lost the 300 from his runners-up finish at last year's event in Mexico which allowed the Swiss to increase his advantage without having to pick up a racquet.

Nadal's fresh injury problems will see him miss the Sunshine Double at the BNP Paribas Open in Indian Wells and the Miami Open this month, with his comeback pencilled in for the start of the clay court season.

But as the men's season breathes back into life this week (8-17 March) in North America, the 10-time French Open champion's hopes of returning to the summit of the sport is not necessarily over. IBTimes UK explains all.

Can Nadal go back to world number one in Indian Wells?

Just as Federer extended his points lead over Nadal without having to hit a ball in anger, the Mallorca-native can reclaim the world number one ranking for a fifth time as he lies on the treatment table.

Federer ousted Nadal from last year's tournament with a straight sets victory in the fourth round in California, ensuring the latter recouped just 90 rankings points from his campaign - all of which he will relinquish this week - leaving him on 9,370.

The 2014 Davis Cup winner however went on to take the title for a fifth time, overcoming Nick Kyrgios thanks to a walkover, before dispatching American Jack Sock and then fellow-countryman Stan Wawrinka in the final.

That display ensured Federer added 1000 points to his total, but he must now defend much of that tally if he is to stand any chance of holding Nadal at bay.

Reaching the semi-finals or better will be enough for Federer to remain at world number one, meaning four wins at Indian Wells is required. Anything less and Nadal will enjoy another stint as the world's top player without having to lift a finger.

The field for the opening ATP World Tour Masters Series 1000 event of the year is star-studded, making Federer's route to the latter stages potentially tricky.

Headlining the confirmed player list is 12-time grand slam champion Novak Djokovic, who is expected to make his long-awaited return from elbow surgery this week. Five times a champion at the event himself, the Serbian has not played since the Australian Open and will be eager to return to competition.

Last year's beaten finalist Wawrinka will be missing to continue his comeback from knee surgery, while Andy Murray is targeting a return from hip surgery in time for the grass court season.

However, the rest of the current top 10 are expected to be in action including Marin Cilic, Grigor Dimitrov, Alexander Zverev and Dominic Thiem. Other notable entrants include Juan Martin del Potro and Roberto Bautista Agut, who won the titles in Mexico and Dubai in the absence of Federer and Nadal.

Rafael Nadal
Nadal was knocked out in the fourth round in Indian Wells by Federer, but could taste success in California without playing. Getty Images