ROME -- Playing against the World No.1 on her favorite surface, you can’t afford to toss out any freebies.

On a glorious sunny Thursday at Foro Italico, Coco Gauff played Iga Swiatek to a 4-all dead heat through the first 50 minutes, matching skittering defense and booming forehands. And then, for a fleeting moment, Gauff took her eye off the ball.

Back-to-back double faults left her swinging her racket in frustration and gifted Swiatek with a considerable opening. Swiatek hit the line twice in four points and emerged with the first set. The second invariably followed, and Swiatek was a 6-4, 6-3 winner over the No.3-ranked player in the world.

This brings Swiatek to a tantalizing juncture in history.

Only Serena Williams (2013) managed to win consecutive titles in Madrid, Rome and Paris. Swiatek could lock down the first two legs in Saturday’s Internazionali BNL d’Italia final against the winner of the evening match between No.2 Aryna Sabalenka and No.13 Danielle Collins. With a win, the 22-year-old from Poland would find herself in the enviable position of being the overwhelming favorite at Roland Garros.

Swiatek, of course, has already won the Italian Open twice and the French Open on three occasions. Winning Madrid for the first time a few weeks ago was a personal breakthrough and you can see the confidence – as embodied in her swashbuckling game --flowing freely.

Swiatek has now won 11 consecutive matches. That’s also how many times she’s played Gauff in their WTA Tour careers and the victory count stands at 10; she’s 4-0 against the American on red clay.

Gauff, who turned 20 in March, was trying to become only the second player in a decade to reach the women’s singles final here in Rome before turning 21. The first? Iga Swiatek.

Gauff is only ranked two spots below Swiatek, but the gap remains considerable. It’s reminiscent of a comment Dominic Theim made to reporters after defeating Alexander Zverev at Roland Garros in 2016. Asked afterwards what the difference was, Thiem smiled and said, “About three years.”

“I thought that I played well majority of the match,” Gauff told reporters later. “It came down to certain moments. Yeah, she came up clutch. She had a lot of balls on the line, close to the line, which is what she does.”

Fact is, Gauff passed Caroline Wozniacki for the most wins in WTA 1000s before the age of 21 when she beat Zheng Qinwen in the quarterfinals. She’s the reigning US Open champion, but is still working to close the gap on Swiatek in this setting. Few players outside of Aryna Sabalenka and Elena Rybakina can consistently put themselves in the Pole's orbit.

Watch this: Swiatek and Gauff trade dueling hot shots in Rome

Gauff has been focusing on her service game in practice, but it’s been wanting, particularly in the big moments. Double faults are often the result of nerves under stress and she leaves the tournament with a total of 45 in five matches.

“The double-faults, they did come just in that one game,” Gauff told reporters. “Overall, if I'm going 120 [miles per hour] on the serves, I have to expect that.

“But overall I would say from just this match, I feel more negative emotions right now. Looking at the whole tournament from where I started to now, I definitely feel like it’s major improvement."

Said Swiatek, “For sure these are nice words. Hard for me to say. She’s the one who’s playing this kind of tennis and feeling what she can do with her racket. It’s a compliment from her.”

Swiatek wound up breaking Gauff four times, while giving up only one break herself. When it happened in the fifth game of the second set, the match was effectively over. It ran 1 hour and 48 minutes but somehow felt quicker.

After the last backhand -- following a sharp forehand service return -- Gauff walked slowly to the net with a resigned look on her face. Swiatek shook hands, acknowledged the chair umpire and happily danced on Stadio Centrale.

When Swiatek paints the lines like she did at the end, are there times when she feels unbeatable?

“No,” Swiatek said. “If I would feel that way, I wouldn’t play so well because I always try to remind myself that I shouldn’t expect anything, take anything for granted. Usually when I feel like this one is going to be a winner, I’m going to win this game, it doesn’t happen, so ... I have to think a little bit differently to be more efficient.”