Tennis is a game of razor-thin margins. A few millimeters can mean the difference between victory and defeat, and often, just a handful of points over several hours separates you and your opponent.

That was the case Sunday in Beijing, where Eva Lys stunned No. 8 seed Elena Rybakina 6-3, 1-6, 6-4 on Sunday in Beijing in one of the more surprising results of this year’s China Open. After 2 hours and 14 minutes of play, Lys clinched the win when Rybakina’s final shot sailed long — leaving the two to finish the match separated by a single point in favor of Lys.

Beijing: Scores | Draws | Order of play

The victory marked a series of firsts for the 23-year-old German:

First win against Rybakina (previously 0-1)
First win against a Grand Slam champion (0-6)
First win over a top 10 opponent (0-8)
First win over a top 20 opponent (was 0-11)
First fourth-round appearance at a WTA 1000 event

After the match, Lys reflected on her milestone moment with gratitude.

“I’ve already outdone myself,” Lys said. “Being in the fourth round for the first time is a nice feeling, so I’m just enjoying everything. I’m enjoying the fans, the good, big courts — I’m just really happy.”

Here are some takeaways from the match:

Key Moments: Lys held at love to take a 4-3 lead late in the first set. After a string of breaks between the two players, it was the first time in the match there had been consecutive holds.

Up to that point, Lys had generated break points in each of Rybakina’s first three service games. She did so again in the fourth, earning two more chances. After Rybakina saved the first with an ace, Lys converted the second with a backhand winner down the line to go up 5-3. She held in the next game to take the opening set.

Rybakina responded quickly in the second, winning the first two games. Lys broke back in the third game, but Rybakina broke at love in the following game and won the final four games of the set to force a decider.

The third set was a tug-of-war, with momentum shifting constantly. After Lys was broken to fall behind 4-3, she immediately broke back — her sixth break of the match — and then won the final three games, breaking Rybakina a seventh time to close out the upset.

Crunching the numbers: Lys finished with 95 total points won, just one more than Rybakina’s 94. Both players won 13 games.

The key statistical differences came in first-serve percentage (71% for Lys, 46% for Rybakina) and unforced errors (20 for Lys, 50 for Rybakina). Rybakina led in winners (28 to Lys’ 21) and aces (8 to 1), but couldn’t overcome the errors that plagued her, especially in the first and third sets.

Both players converted seven breaks of serve. Rybakina was more efficient, going 7-for-9, while Lys converted 7 of a whopping 20 chances.

It was the second straight match Lys has been broken seven times and still won.

Looking ahead: Lys will face McCartney Kessler in the fourth round.

She leads the head-to-head 1-0, having won their lone meeting last year in Japan in three sets.

A second win over the American would not only mark Lys’ first trip to a WTA 1000 quarterfinal, but it would likely secure her debut in the top 50 of the PIF WTA rankings as well.

Kessler advances after Krejcikova retires in the third set

It wasn’t the way McCartney Kessler would’ve preferred, but she’s through to the fourth round of the China Open after Barbora Krejcikova retired in the third set of their match Sunday in Beijing.

Kessler led 1-6, 7-5, 3-0 when the former Grand Slam champion was forced to stop due to a left knee injury sustained in the opening game.

Initially, Krejcikova had the knee heavily wrapped and chose to play on. She appeared steady in the first set — breaking Kessler twice and winning the set in 37 minutes.

Kessler left the court after the first set to regroup mentally, and it paid off. She jumped out to a 2-0 lead in the second set, but Krejcikova responded. She won four straight games to go up a set and a break and looked poised for victory.

Instead, Kessler surged, winning eight of the next nine games to take the second set after 66 minutes and race to a 3-0 lead in the third set. At that point, Krejcikova determined the risk of continuing on a worsening knee wasn’t worth it.

With the retirement, Kessler advanced to her second career WTA 1000 fourth round, where she’ll face Lys.

Later, Paula Badosa joined Krejcikova on the sidelines. The No. 18 seed was forced to retire trailing No. 13 seed Karolina Muchova 4-2 due to a left hip injury.