By the numbers: Rybakina defeats Polina Kudermetova in Berlin opener

No.2 seed Elena Rybakina made a winning start on her return to grass, defeating qualifier Polina Kudermetova 6-4, 6-2 in the first round of the bett1open.

Here are the key numbers from the Wimbledon champion's 66-minute win.

9 - Rybakina's active winning streak now stands at nine, dating back to her Rome title in May. This match was her first since withdrawing from Roland Garros due to illness ahead of her third-round clash with Sara Sorribes Tormo. It was also her eighth straight grass-court win following last year's title run at Wimbledon.

9 - The younger sister of World No.13 Veronika, Kudermetova was playing her third career tour-level main draw, having won her first match at this level last week in 's-Hertogenbosch. The No.139-ranked 20-year-old impressed by going toe-to-toe with Rybakina, particularly in the first set, with her serve a key weapon. Both players landed nine aces: six in the first set and three in the second.

38% - The key statistical difference was in each player's second serve. Both maintained a winning percentage above 70% behind their first delivery -- but while Rybakina also won a healthy 69% of the points behind her second, Kudermetova only managed 38%.

14/15 - A tightly contested opening set, which featured a three-hour rain delay after just one game, was poised to swing either way as Rybakina served at 4-4, deuce. But the World No.3 demonstrated her ability to rise to the occasion, taking 14 of the next 15 points to snatch the first set and seize momentum for the first time. She would not let up, dropping just four points behind serve in the sceond set.

3/11 - If Rybakina had a vulnerability, it was in her break point conversion rate. She brought up 11 chances on the Kudermetova serve, but only took three. The younger player did have a knack of finding her biggest serves at these moments, however.

1-0 - Rybakina's head-to-head lead over her second-round opponent, Donna Vekic. Rybakina previously won 7-6(3), 6-4 in the third round of the Tokyo Olympic Games in 2021.

Avanesyan saves two match points, upsets Kasatkina

In the same quarter, lucky loser Elina Avanesyan saved two match points and upset No.8 seed Daria Kasatkina 6-2, 3-6, 7-6(7).

Highlights: Avanesyan def. Kasatkina

Avanesyan was not even in the main draw until early on Tuesday. She replaced 30th-ranked Petra Martic, who withdrew from her scheduled match against Kasatkina due to a lower back injury.

World No.81 Avanesyan took advantage of her opportunity, knocking out Kasatkina in 2 hours and 25 minutes and earning the second Top 20 win of her career. Her first Top 20 win came mere weeks ago, when she shocked Belinda Bencic in the first round of Roland Garros.

It was at Roland Garros where Avanesyan started her lucky loser magic, which has now extended into Berlin. At Roland Garros, Avanesyan became the first lucky loser to reach the Round of 16 at any Grand Slam event since 1993.

After splitting the first two sets on Tuesday, Kasatkina came back from an early break down to take a 5-2 lead in the third set. However, Kasatkina was unable to serve out the match at 5-3, and the pair advanced into a tiebreak.

Kasatkina then held her pair of match points at 6-4 in the tiebreak, but Avanesyan saved them both with strong rally action. Avanesyan had her first match point at 7-6 erased, but her second match point at 8-7 was converted after Kasatkina fired a forehand miscue into the net.