The Briton, who was playing fairly before the mid-match trim, slumped to a defeat against Nadal in their Round Robin match in the ATP Tour Finals on Wednesday.
Jannik Sinner overpowered American Taylor Fritz in the final to become the first Italian man to win the US Open singles title.
Roger Federer gave a cautious thumbs up on Sunday to the ATP's decision to shorten the men's calendar by two weeks from 2012.
'I think he's bringing a fresh look to my game and I'll be able to benefit from that, no doubt, on the court. But also that champion mentality he has, I'm sure we'll match very well.'
The last time the Swiss maestro was this far down in the ATP rankings was all the way back on January 2001, when Federer was just 19 years old. Notably, he was yet to win his first tour title.
The Serb easily beat the Spaniard 6-3, 6-4 at the O2 Arena.
Novak Djokovic's bid to add a 100th singles title to his trophy cabinet on Sunday was dashed after he was beaten 7-6(4), 6-3 by world number one Jannik Sinner in the Shanghai Masters final on Sunday.
Retired tennis great Andy Murray has agreed to join Novak Djokovic's team and will coach him at the Australian Open next year, the Serbian 24-times Grand Slam champion said on Saturday.
Novak Djokovic dug out a 6-7(4) 6-1 6-4 win over Czech Jakub Mensik on Friday to advance to the semi-finals of the Shanghai Masters, where he will face Taylor Fritz.
Sasikumar Mukund will aim for a winning return to the Davis Cup fold as India faces Togo in the World Group I Play-off.
Japan's Kei Nishikori surged to a three-set victory over alternate David Ferrer at the ATP World Tour Finals on Thursday before sitting back to watch his fate unfold in the night match.
The ATP Tour brought the world number ones for a short conversation as they prepared for the prestigious tournament.
Former world number three Nikolay Davydenko announced his retirement on Thursday at the age of 33.
Roger Federer wants more blood testing done in tennis to help keep the sport clear of doping, the 17-time Grand Slam champion said on the eve of the ATP World Tour Finals.
Indian Davis Cupper Rohan Bopanna dropped out of the top-10 in the ATP doubles ranking after finishing last along with Pakistani partner Aisam-ul-haq Qureshi in group B of the season-ending finale in London.
Briton Andy Murray will take over from Novak Djokovic as World No 1 when the rankings are updated on Monday after his Paris Masters semi-final opponent Milos Raonic withdrew with a leg injury on Saturday.
India has never beaten Sweden in five attempts in the Davis Cup.
Sasikumar Mukund, who was banned by AITA on disciplinary grounds, is back as India's best-ranked player for the World Group I Play-off tie against Togo, starting on Saturday.
Frenchman Julien Benneteau caused a stir during an interview on French radio station RMC Sport on Sunday in which he said tournament referees were often kinder to Federer when it came to scheduling his matches.
Britain's Jamie Murray and Brazil's Bruno Soares will end the year as the top-ranked doubles duo after French pair Nicolas Mahut and Pierre-Hugues Herbert lost at the ATP World Tour Finals on Friday.
World No 1 Rafael Nadal, who is hoping to recover from a knee injury to play in the season-ending showpiece, heads the other group and will face Belgian David Goffin, Bulgarian debutant Grigor Dimitrov and Austrian Dominic Thiem.
The Swiss star underwent arthroscopic right knee surgeries in February 2020 and May 2020. Federer has played five tournaments since having those surgeries, all of which came this season.
Dimitrov was showing signs of fatigue from his three-hour third-round match earlier in the week and could do little to stop the Spanish world number three, who next faces Argentine Francisco Cerundolo.
Italy's Sinner and Spain's Alcaraz have won two Grand Slams each this year, with Alcaraz beating Sinner in closely fought clashes at the French Open semi-finals and the China Open final.
World number six Milos Raonic has withdrawn from the French Open having failed to recover from a foot injury, the 24-year-old announced on Thursday.
Leander Paes might team up with Ramkumar Ramnathan instead of Sumit Nagal in this month's Asian Games after captain Zeeshan Ali said he will consider the ATP World Tour finalist's request to pair up with the senior pro.
Roger Federer's decision to withdraw means Switzerland can no longer take part in the nation-based event on January 3-12
Roger Federer produced another masterly display to beat Japan's Kei Nishikori 6-3 6-2 and move a step closer to the semi-finals at the ATP World Tour Finals in London on Tuesday.
Third seed Alexander Zverev eased past home favourite Ugo Humbert
The winner of 11 ATP World Tour doubles titles, Poles Marcin Matkowski and Mariusz Fyrstenberg were off to a great start with a 6-3, 7-6 (3) victory over Indo-Czech duo of Leander Paes and Lukas Dlouhy at the opening day Round Robin match at the 2010 World Tour Finals in London on Sunday.
The prestigious end-of-season Masters Cup will switch from Shanghai to London from 2009, the ATP men's tennis tour announced on Tuesday.
Former world number one Novak Djokovic, the last surviving member of tennis' "Big Four", said he does not plan on stopping any time soon but admitted that the retirement of rivals Roger Federer, Andy Murray and Rafa Nadal has been overwhelming.
American Jack Sock clinched the last spot in the ATP Tour finals when he beat Serbian qualifier 5-7, 6-4, 6-1 to win the Paris Masters title on Sunday.
It has now come to light that Federer's wife Mirka is at the centre of this now infamous row between the seventeen-time Grand Slam champion and the 2014 Australian Open champion.
Sinner remains the man to beat at Melbourne Park even as doping officials seek a two-year ban for the world number one for failing two drugs tests last March.
AITA President Anil Jain, who was accused of using his position for personal gains, avoided facing a no-confidence motion from the state associations only after he agreed to step aside.
Friction has dogged the ATP Player Council, whose president is world number one Novak Djokovic, this year since ATP president Chris Kermode failed to gain support for another term.
Leander Paes and his partner Lukas Dlouhy rounded off their disappointing campaign at the season ending World Tour Finals with their third successive defeat in London on Friday.
Yuki Bhambri and his Dutch partner Robin Hasse went down in straight sets to Ivan Dodig and Austin Krajicek at the Dubai Duty Free Tennis Championships.
The first player to win a Grand Slam, the ATP World Tour Finals, the men's singles at the Olympic Games and a Masters title in the same calendar year.