14 Nov 2020: ATP Finals: Nadal desperate to prove himself indoors
Notably, just one of Nadal's 86 career titles have come on indoor courts, back in Madrid in 2005.
Nadal, who is set to face Andrey Rublev, opened up on indoor courts.
Route: Nadal has a harder route to the semis
Nadal appears to have the harder route to the semi-finals with Andrey Rublev completing the London 1970 group alongside Stefanos Tsitsipas and 2020 US Open winner Dominic Thiem.
ATP Finals: Group London 2020: Can Nadal win maiden ATP Finals trophy?
Spaniard Rafa has gone empty-handed at the season-ending tournament ever since his debut back in 2005.
The 2020 French Open winner has come close to winning the title on several occasions, having finished runner-up to Federer in 2010 and to Djokovic in 2013.
Nadal leads Tsitsipas and Rublev 5-1 and 1-0 respectively in the head-to-head, and his biggest test will be against Thiem.
Words: I think I have played less indoors, says Nadal
Nadal said he has played less indoors than in other places, highlighting that numbers are the numbers.
"We can find excuses or reasons but at the end of the day the numbers are the numbers," Nadal said.
"I think I have played less indoors than in other places without a doubt. The indoor surfaces have been not ideal surfaces for my tennis game."
Hope: Nadal hopes to change his fortunes
Nadal is hoping to change the numbers he has registered on indoor courts.
"I think I am able to play a little bit better the last couple of years indoors than what I did at the beginning of my tennis career without a doubt but that's the numbers and I can't say something different. I hope to change that this week," he added.