Filling the cavernous venue with his grunts, he forced his way past defending champion Stefanos Tsitsipas 6-4 4-6 6-2 to make the last four of the ATP Finals.
Nadal ended Tsitsipas' hopes of retaining his title with a 6-4 4-6 6-2 victory to reach the final four of the tournament for the first time since 2015.
Tsitsipas' record against Nadal now stands at 1-6, with his only victory coming, somewhat unexpectedly, on clay in Madrid last spring.
This afternoon, in another straight shootout to conclude the group stage, Novak Djokovic and Alex Zverev will face each other to determine the last semi-finalist, with a match against Dominic Thiem the prize.More news: South Dakota Among Top States for Early Diagnosis, Lung Cancer Screening Rates
Tsitsipas was again under pressure in his next service game and this time he cracked, double-faulting on break point.
Tsitsipas, 22, felt disappointed with the third set. "That game, 5-4 in the second set, affected me a little bit", Nadal said in his on-court interview. Although a double fault caused him to lose the second set, he was tough enough to see off a rushing Tsitsipas in the deciding set.
It was a dynamic effort from Tsitsipas, whose second serve could not withstand Nadal's onslaught in the decider as the Greek fell short of the semifinals.
The U.S. Open champion lost to Rublev 6-2, 7-5 in a contest that had little real outcome for either player, with Thiem assured of being the victor of the group after previous victories over Stefanos Tsitsipas and Rafael Nadal and his Russian opponent unable to qualify for the semifinals after back-to-back losses.
"I took advantage from the beginning and that helped me to have more confidence and helped me to play better and better".More news: Gordon Hayward reportedly declines player option, becomes free agent
Andrey Rublev of Russian Federation is interviewed after winning his match against Dominic Thiem during the ATP World Tour Finals in London, England, November 19, 2020.
"With the fact that I was already qualified in the back of my mind, it was maybe hard today to keep that intensity alive", said Thiem, who had already clinched top spot in Group London 2020.
Debutant Rublev was already eliminated after two losses while Thiem's brilliant victory over Rafael Nadal on Tuesday guaranteed him top spot in the group. Crucially he saved a couple of set points in the first tiebreak before whipping away a forehand to take an opening set in which there was barely a cigarette paper between the two.
But this year the situation was much simpler, the victor between the duo will join World number three Dominic Thiem to reach the last four.
Murray and Skupski failed to qualify for the ATP Finals by the tiniest of margins, and that seems to have precipitated the reunion with Brazil's Soares.More news: Australia alleges military carried out unlawful killings in Afghanistan