Stefanos Tsitsipas beat six-time champion Roger Federer to reach the final of the ATP Finals in London.

The Greek, making his debut at the event aged just 21, won 6-3 6-4.

Swiss Federer, 38, was aiming for a record-extending seventh title but was undone by the nerveless Tsitsipas, just as he was at January’s Australian Open.

Defending champion Alexander Zverev and fifth seed Dominic Thiem meet later on Saturday for the chance to play Tsitsipas in Sunday’s final.

Federer was supreme in beating great rival Novak Djokovic to reach the semi-finals on Thursday but was well below his best on this occasion and was left rueing a host of missed opportunities on crucial points.

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Tsitsipas wins battle of the generations

The 17-year age gap between the two players is the biggest in the history of the season-ending championships.

With the London crowd heavily in favour of Federer, Tsitsipas played the better tennis, particularly on the big points.

The Greek saved break point in the very first game before clinching Federer’s opening service game minutes later with a forehand winner.

In total, Federer had six break points in the opening set but failed to take any as Tsitsipas held firm and the 20-time Grand Slam champion gifted points with errors.

Serving for the set at 5-3, Tsitsipas fought off two of those break points but saw six set points of his own come and go in a marathon game before clinching the opener on his seventh.

Federer errors gave his opponent an further early break in the second set, only for the Swiss to finally convert a break point a game later at the 10th attempt.

But, after the crowd roared in hope of a comeback, Tsitsipas crunched another forehand winner to seal Federer’s service game.

Typically, Federer had two more break points when Tsitsipas served for the match but the Greek closed out the win with some big deliveries.

He was already the youngest player to have recorded wins against Federer, Djokovic and Rafael Nadal but this victory strengthens further his standing as one of the best young players in the game and leaves him one win away from the biggest title of his career.

“Today’s victory is probably one of my best moments of the season,” said Tsitsipas, who 12 months ago won the Next Gen Finals – the season-ending event for the best players under 21.

“These are the moments I live for.”

More to follow.

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