Matteo Berrettini became the first Italian to win a singles match at the ATP Finals with a straight-sets 7-6 (7-3) 6-3 victory over Dominic Thiem in Group Bjorn Borg.
The 23-year-old knew going into the match that he didn't have a chance of qualifying for the semi-finals, however he did not let that stop him from producing some excellent tennis.
The last Italians to feature in the year-end tournament in singles were Adriano Panatta in 1975 and Corrado Barazzutti in 1978 and both lost all three of their round-robin matches.
In this edition of the tournament, Berrettini avenged his last defeat to Thiem and duly levelled up their tour head-to-head to two wins apiece.
After back-to-back victories over Roger Federer and Novak Djokovic, Thiem had already booked his place in the last four and now must wait to find out his opponent.
He will face the player who finishes second in Group Andre Agassi - one of Rafael Nadal, Daniil Medvedev or Alexander Zverev.
The trio will all take to court on Friday, Nadal against the already-qualified Stefanos Tsitsipas and Medvedev facing Zverev, with a wealth of potential permutations when it comes to the final table standings.
In the opening set between Berrettini and Thiem, the Italian used his variety to make an initial move to clinch it in the ninth game.
His swift and tidy work on Thiem's serve, which included a sumptuous passing winner at 0-40, gained what could have been a key break. However, his actions spurred Thiem to spring back into action and he broke Berrettini straight back.
From there, the two could not be separated again and a first-set tiebreak was the result.
In it, Berrettini forced early errors from his opponent to go 2-0 in front and then added to that cushion with a sliced backhand winner down-the-line. The Italian maintained his momentum and secured the set with his second ace by 7-3.
After the emotional intensity that he found against Djokovic on Tuesday, and Federer before that, Thiem didn't reach the same heights in this third round-robin match.
Instead he looked like he was trying to save some energy ahead of Saturday's semi-finals and against a focused Berrettini was broken again midway through the second set.
The Italian consolidated the break as he continued to secure a high percentage of points off his first serve and went into the change of ends, after just 23 minutes of second-set tennis, with a 5-3 advantage.
The afternoon prior, Nadal showed that a comeback from such a challenging position was possible however lightning didn't strike twice in London and instead Berrettini retained his hold over Thiem and served it out to finish his noteworthy ATP season on a high.
Stats of the match
Berrettini started the year ranked 54 in the world and has said that his first ATP Finals has been a great experience and platform to learn from.
Proud moment for Berrettini
What's next?
The evening session on Thursday will complete the standings in Group Bjorn Borg and features a blockbuster encounter between Novak Djokovic and Roger Federer.
This will be their 49th meeting, their first since their exceptional Wimbledon final, and just one of the two will be able to progress into the semi-finals.
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