One day after her 19th birthday, Leylah Fernandez gave herself the ultimate present: victory in a 6-3, 3-6, 7-6(5) thriller over No.5 seed Elina Svitolina to reach her first Grand Slam semifinal at the US Open.

The teenager's self-belief and trust in her shots were on full display in a stellar third set. The tenacious Svitolina hauled her way back from 2-5 down to force a deciding tiebreak, and therein came from 1-4 down to level at 5-5, but Fernandez never blinked. It was the first time she had won a third-set tiebreak at Tour level.

The result is Fernandez's third career Top 5 win, two of which have come this fortnight. She is the third Canadian to make the semifinals in Flushing Meadows following Carling Bassett-Seguso in 1984 and 2019 champion Bianca Andreescu, and she is also the youngest US Open semifinalist since an 18-year-old Maria Sharapova in 2005. She also avenges a loss to Svitolina in their only previous meeting, 6-4, 7-5 in the 2020 Monterrey quarterfinals.

Fernandez is now the youngest current player to have reached the last four of a major, wresting that title from 2019 Roland Garros semifinalist Amanda Anisimova. Qualifier Emma Raducanu, 18, has the opportunity to seize the record tomorrow when she takes on No.11 seed Belinda Bencic.

Remarkably, this is just Fernandez's third Tour-level semifinal, and first above 250 level. Previously, she had reached her maiden WTA final at Acapulco 2020, and captured her first title in Monterrey this March. Currently ranked World No.73, she will crack the Top 50 for the first time next Monday.

For Svitolina, the loss marks more Grand Slam frustration. Despite a much-improved performance at this stage - of her seven previous defeats at the quarterfinal stage or later of a major, six had been in straight sets - her record in the last eight of a Slam now drops to 2-6. 

Words from the winner: "Today's match was definitely one of the hardest, not only tennis-wise but also mentally and emotionally," Fernandez said, in her post-match press conference. "Svitolina is a great player, great fighter. I was glad I was able to fight in the first set. In the second set she upped her level and I unfortunately made a few mistakes on key moments.

"I'm glad I was able to recuperate for the third set. The tiebreak, too. A little bit lucky at 5-5, but I'll take all the luck I can get. I was glad I was able to push through the finish line."

"Honestly after my [first WTA singles title in February] in Monterrey, I was training well, playing well," Fernandez added. "Just a few bad matches here and there. I always went back to work. Went back home to work harder, try to improve my game.

"I was glad that every match that I played, I was improving little by little. Today, or this whole few weeks, I was able to showcase all the sacrifice I've made the past year so that I can get to this point."

"For today and this match, I was only thinking of trusting myself, trusting my game," Fernandez said. "After every point, win or lose, I would always tell myself, trust my game, go for my shots, just see where the ball goes."

Tactical challenges: The two players combined for 74 winners in total - 42 from Fernandez's racquet compared to 32 for Svitolina. A pulsating third set saw both players tally 18 winners, but their match trajectories to reach that level had been different.

Fernandez had raced out of the blocks, picking up where she had left off against Angelique Kerber in the previous round. As in that match, the youngster's ability to create brilliant angles out of nowhere and essay perfectly judged changes of direction enabled her to dominate play.

For Fernandez, the challenge as she got deeper into the match was to maintain that high-risk approach. For Svitolina, it was the reverse. In an overly passive first set, she found only four winners to 11 unforced errors. It was a pattern that was uncomfortably reminiscent of previous one-sided Grand Slam second-week losses, such as to Nadia Podoroska at Roland Garros 2020.

This time, Svitolina managed to force herself out of her comfort zone. The Ukrainian moved up the court and went for bolder shots in order to turn the match around in the second set, which she led 5-1 before eking over the line two games later, and to come close to doing so again in the third.

Nail-biting finish: Though Svitolina had managed to gather her game to ultimately close the second set out with an ace, her wobble before doing so had enabled Fernandez to find some rhythm to take into the decider. The unseeded player won a scintillating net exchange to break first for 3-1 - and even when Svitolina broke back, Fernandez found a series of spectacular forehands to regain the lead for 4-2. A delightful dropshot-pass combination saw her hold for 5-2.

The next passage of play saw Svitolina blend tenacity and aggression to mount a comeback. She stood at 30-30, two points from defeat, at 2-5, 3-5, 4-5 and 5-6. Each time, the 26-year-old won the next two points to stay alive. As Fernandez had built her lead, she had exhorted the crowd after every top-quality point; Svitolina did likewise as she desperately hung on.

The deciding tiebreak would see another attempted comeback from Svitolina, who trailed 1-4 before levelling at 5-5. But a brilliant backhand pass that clipped the net gave Fernandez the first match point of the day, and she sealed it at the first time of asking with a service winner.

Stat corner: The deciding tiebreak also showcased a key Fernandez strength and a significant Svitolina weakness. At 4-4, Fernandez managed to out-grind Svitolina in a 19-shot baseline duel. That's usually territory in which Svitolina thrives, but it was one of several extended exchanges in which she broke down first.

As ever, Svitolina's first serve was crucial. She won 72% of the points behind it, including eight aces, and her first serve percentage actually rose as the match went on. But Fernandez was repeatedly able to punish Svitolina's second serve - frequently with clean return winners, including after a 71mph delivery on the third point of the tiebreak. Svitolina won only 41% of those points.

Fernandez's fight: Fernandez's run this fortnight has been characterised by finding her best tennis with her back to the wall. In the first round, she trailed Ana Konjuh 3-5 in the first set and saved two set points before winning 7-6(3), 6-2. In the second, Kaia Kanepi led 5-3 in the second set and held four set points before Fernandez came back to win 7-5, 7-5. In the third and fourth, Fernandez trailed both Naomi Osaka and Angelique Kerber by a set and a break before upsetting the multiple Grand Slam champions 5-7, 7-6(2), 6-4 and 4-6, 7-6(5), 6-2 respectively.

What's next for Fernandez: An opportunity to keep her fairytale run alive against No.2 seed Aryna Sabalenka, with a first Grand Slam final at stake. Sabalenka defeated No.8 seed Barbora Krejcikova in the night session quarterfinal; Fernandez has yet to face Sabalenka.

Champion's Reel: How Leylah Fernandez won Monterrey 2021

2021 Monterrey