Rafael Nadal is on the verge of finishing the year as the world number one after opening his ATP World Tour Finals campaign with a 6-3, 6-2 win over David Ferrer on Tuesday.
Nadal arrived at London's O2 Arena still smarting from a surprise loss against fellow-Spaniard Ferrer in the semi-finals of the Paris Masters on Saturday, but he was quick to avenge that defeat with an emphatic victory in 74 minutes.
The win means the 27-year-old will be guaranteed to end 2013 top of the world rankings, ahead of Novak Djokovic, if he beats either Tomas Berdych or Stanislas Wawrinka in his remaining Group A fixtures at the prestigious season-ending event.
It will be the third time Nadal has finished a year as number one, but the first since 2010.
"They are never easy games against David Ferrer, the number three in the world. He is great and having an amazing career," Nadal said.
"He played a lot better than me in Paris last week but today I played a little bit better than him and it's important for my confidence to start with a victory after Paris.
"The energy of this stadium is fantastic and hopefully I am ready for tomorrow (Wednesday) against Stanislas Wawrinka."
If Nadal does end up in top spot, it will complete what the 13-time Grand Slam champion regards as the most satisfying year of his illustrious career.
When Nadal returned in February after a seven-month battle to recover from tendinitis in his knee, his ranking had dropped to number five in the world -- his lowest position since 2005 -- and he was worried if he would ever recapture his top form.
But he showed no signs of having lost a step as he stormed to his eighth French Open title and then won the US Open, as well as claiming eight other titles.
With his place among the elite firmly re-established, a maiden triumph at the Tour Finals would be the perfect way to cap the campaign.
Nadal had this week called for the Tour Finals to be played on a different surface each year to be fair to players who specialise in clay and grass court tennis, but he looked comfortable enough on the O2 Arena's hard courts as he broke Ferrer in the opening game of the match.
Ferrer had won just five of his 25 meetings with Nadal, although he was unbeaten in their only two previous indoor encounters, and the world number three hit back with an immediate break of his own.
That was the last time the 31-year-old really troubled Nadal, who was gifted another break for a 4-2 lead thanks to a pair of careless forehands from the out-of-sorts Ferrer, who made 33 unforced errors in total.
Nadal continued to blitz Ferrer with his booming backhands and broke again to take the set.
Ferrer was looking increasingly unsettled by Nadal's barrage and he cracked again in the second game of the second set before another break for a 4-0 lead which effectively sealed the world number one's win.
Nadal had claimed he wasn't concerned about finishing top of the rankings, but his fist-pumping celebration and broad grin when he converted his second match point suggested otherwise.