Five Americans contested second-round matches at Wimbledon on Thursday, with all of those matches in the top half of the draw. There were mixed results for the players from the United States as scores came in throughout the day.
The most recent American to win the Wimbledon singles title is Serena Williams, who claimed it for a seventh time in 2016. Serena is also the most recent American to reach the Wimbledon final, when she finished runner-up in 2019.
Here is a breakdown of the five matches on Day 4 which included the Americans:
 Donna Vekic (CRO) def. Sloane Stephens (USA) 4-6, 7-5, 6-4
On No.1 Court, Croatia's Vekic pulled off a two-and-a-half-hour comeback thriller over 2017 US Open champion Stephens, clinching a third-round spot for only the second time in her career. Vekic battled all the way back from 6-4, 5-2 down to take the victory.
From that deficit, No.20 seed Vekic reeled off five games in a row to level the match at one set apiece. The third set started with both players gritting out holds -- Stephens saving four break points for 1-0, and Vekic erasing three break points to reach 1-1.
But the following game proved decisive, as Vekic used a clutch of forehand winners and two return winners off the netcord to get from 40-0 to break point. There, Stephens sent a miscue long, giving Vekic the critical 2-1 lead.
The rallies and games remained grueling, but Vekic never faced another break point as she moved to the hard-fought victory. The Croatian wrapped up the match with a powerful forehand -- her 34th winner of the day.
Vekic will next face Czech lefty Marketa Vondrousova in the third round, after Vondrousova upset No.12 seed Veronika Kudermetova 6-3, 6-3 earlier on Thursday. Vekic won their only previous meeting 6-4, 6-4 at Hobart in 2018.
 Belinda Bencic (SUI) def. Danielle Collins (USA) 3-6, 6-4, 7-6
Running concurrently with Vekic's match, Switzerland's Bencic won a barnburner of her own on No.2 Court in 2 hours and 44 minutes. Bencic leveled her head-to-head with 2022 Australian Open finalist Collins at 1-1 with the victory.
Like Vekic, No.14 seed Bencic came back from a set and a break down before collecting her second-round win. Bencic moves into the third round of Wimbledon for the fifth time in her career, but it is her first trip this far at SW19 since 2019.
At 2-2 in the third set, Bencic found herself in a crucial 15-minute service game, where she survived nine deuces and erased three break points before holding. There were no service breaks in the third set, but Bencic turned up the heat in the 10-point match tiebreak, dominating from start to finish.
Bencic has struggled with a hip injury this summer, and she is playing only her second event since her runner-up finish at Charleston in April. This week, she has picked up her first two match-wins since that tournament.
2021 Olympic champion Bencic will face No.23 seed Magda Linette of Poland in the third round. It will be Bencic's first meeting with this year's Australian Open semifinalist Linette.
 Jessica Pegula (USA) def. Cristina Bucsa (ESP) 6-1, 6-4
Pegula, the top-ranked American at World No.4, held off a second-set charge by 78th-ranked Bucsa of Spain before notching a comfortable 63-minute win on No.1 Court.
8 - Jessica Pegula is the first American player to reach 8+ consecutive Third Rounds in Grand Slam events since Serena Williams (nine between Roland Garros 2018 and the US Open 2020). Constancy.#Wimbledon | @WTA @WTA_insider pic.twitter.com/BUnSetxV9E— OptaAce (@OptaAce) July 6, 2023
In the first meeting between the pair, Pegula was headed for a win in under an hour, holding two match points at 5-2 in the second set. But Bucsa crept back into contention, reaching 5-4 and 0-30 on the Pegula serve before the American was able to regroup and power to victory.
Crafty Bucsa won six of her seven net points in the match, but Pegula finished the day with 14 winners to Bucsa's 11. Most importantly, Pegula converted five of her nine break points while Bucsa was 2-for-5.
Pegula will have her first meeting with World No.43 Elisabetta Cocciaretto in the third round. Pegula has yet to reach the Round of 16 at Wimbledon; in fact, it is the only major where she has not reached the quarterfinals.
[Q] Sofia Kenin (USA) def. Wang Xinyu (CHN) 6-4, 6-3
The 2020 Australian Open champion Kenin was the first winner of the day at Wimbledon. The former World No.4 from the United States took 1 hour and 14 minutes to ease past China's Wang, who teamed with Hsieh Su-wei to win the French Open doubles title last month.
Currently ranked No.128, Kenin had to play the qualifying rounds, where she easily won her three matches in straight sets. Kenin immediately brought that form into the main draw, where she stunned No.7 Coco Gauff in three sets in the first round.
Kenin backed up her tenth career Top 10 win by dispatching Wang for the third time in their three meetings, despite having fewer winners and more unforced errors than the Chinese player. Kenin won 68 percent of Wang's second-service points, leading to a 4-for-7 break point conversion rate.
"I played really well," Kenin said afterwards. "I'm super proud of myself the way I was able to handle my nerves, because I was a bit nervous at some times. I stuck to my guns, and I did a great job."
Kenin will now meet another former Top 5 player on the comeback trail, Elina Svitolina of Ukraine, in the third round. Svitolina leads their head-to-head 3-2, but all five of their meetings took place in 2019.
Ana Bogdan (ROU) def. Alycia Parks (USA) 1-6, 6-3, 6-2
In a second-round match between players ranked only six spots apart, No.57 Bogdan of Romania battled past 51st-ranked Parks of the United States in 1 hour and 41 minutes. Bogdan is into the third round of Wimbledon for the first time in her six main-draw appearances.
Bogdan had already upset No.15 seed Liudmila Samsonova in the first round. The 30-year-old Bogdan has built a solid 7-2 win-loss record during this year's grass-court swing.
Bogdan will face Lesia Tsurenko of Ukraine in the third round, after Tsurenko ended the six-match winning streak of Bad Homburg champion Katerina Siniakova 6-4, 6-1. In their only previous match, Tsurenko routined Bogdan 6-1, 6-0 at Istanbul back in 2011.