Emma Raducanu came down to earth in her first tournament since her surprising U.S. Open victory, losing in straight sets to Aliaksandra Sasnovich at the BNP Paribas Open on Friday night.

Raducanu lost 6-2, 6-4 in the second round, ending her 10-match winning streak that began in New York. She received a wild-card into the combined ATP and WTA tournament in the Southern California desert.

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It was Raducanu's fifth Tour-level event since making her WTA Tour debut in June.

"I'm kind of glad that what happened today happened so I can learn and take it as a lesson so going forward I'll just have more experience banked," she said.

Former world No. 1 Andy Murray beat Adrian Mannarino 6-3, 6-2 in his first match as a wild-card. Murray fired five aces and connected on 82% of his first serves against the French lefty-hander. Murray converted three of six break points; Mannarino failed in his lone chance to break.

Leyla Fernandez, who lost to Raducanu in the U.S. Open final, defeated Alize Cornet 6-2, 6-3. Fernandez converted 5 of 9 break points and hit 71% of her second serves.

Sasnovich, a 27-year-old from Belarus ranked 100th in the world, reached the doubles semifinals last month at the U.S. Open while Raducanu was completing a stunning run from qualifier to champion at age 18.

"Emma just won the U.S. Open and I lost there in the first round," Sasnovich said, "so it was a little bit different."

Sasnovich got service breaks to take leads of 3-1 and 5-2 and close out the set in 30 minutes without ever losing her serve.

Raducanu rallied in the second set, taking a 4-2 lead. But Sasnovich broke for a fifth time and led 5-4 before serving out the match. Sasnovich won 53% of her second serves to just 29% for Raducanu.

"I'm still so new to everything," Raducanu said. "The experiences that I'm going through right now, even though I might not feel 100 percent amazing right now, I know they're for the greater good."

Sasnovich advanced to play No. 11 seed Simona Halep in the third round. Halep beat Marta Kostyuk 7-6 (2), 6-1.

Iga Swiatek needed just 71 minutes to dispatch Petra Martic 6-1, 6-3.

The last time the tournament was played in 2019, Swiatek lost in qualifying. Now, she’s the No. 2 seed and the 2020 French Open champion.

Swiatek won nine of the first 10 games against Martic before the Polish star got broken twice and fell behind 0-3 in the second set. Swiatek rallied to win the next six games and close out the match.

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"In 2019, I wasn’t playing that confident, but I’m really happy that times have changed now," Swiatek said. "In the second set, I lost focus for one game and she broke me pretty fast, so I knew I just had to keep going and not stop for a second time."

No. 4 seed Elina Svitolina beat Tereza Martineova 6-2, 7-5. No. 7 Petra Kvitova beat Arantxa Rus 6-2, 6-2. Ninth-seeded Anatasia Pavlyuchenkova topped American Madison Keys 6-3, 6-1.

Victoria Azarenka advanced via walkover when Magda Linette quit trailing 7-5, 3-0. Shelby Rogers routed Kristina Kucova 6-2, 6-2. No. 19 Jessica Pegula beat Sloane Stephens 6-2, 6-3.

On the men's side, Americans Jenson Brooksby and Ernesto Escobedo won their first-round matches. Brooksby beat Cem Ilkel 7-6 (5), 6-4, and Escobedo defeated Holger Rune 6-4, 6-1.