The entirety of the fourth round is played on Day 7 at the BNP Paribas Open. The lineup features six Grand Slam winners (and three finalists), but only one player left -- defending champion Iga Swiatek -- has previously lifted the Indian Wells trophy. Five of the last 16 players remaining are Czech.
Here is your guide to the full Round of 16.
More from Indian Wells: Scores | Order of play | No one does it like Karolina Muchova | Coco Gauff's final year as a teenager | Garcia holds off Fernandez | Rybakina ousts Badosa | Raducanu edges Haddad Maia | Vondrousova defeats Jabeur | Swiatek moves past Andreescu
 Iga Swiatek (POL) vs. Emma Raducanu (GBR)
Head-to-head: Swiatek leads 1-0
One of two fourth-round clashes between Grand Slam champions, Swiatek won their only previous encounter 6-4, 6-4, in the Stuttgart quarterfinals last year. The World No.1's record this year is 14-3, and she is bidding to reach a third straight tour quarterfinal.
Raducanu's run this week marks the fourth time in her career she has won three consecutive WTA main-draw matches, following Wimbledon 2021 (fourth round), the US Open 2021 (champion) and Seoul 2022 (semifinals).
Raducanu's third-round defeat of Beatriz Haddad Maia was the third Top 20 win of her career and first since beating Maria Sakkari in the 2021 US Open semifinals. She is 0-3 against Top 10 opponents so far.
Sorana Cirstea (ROU) vs.  Caroline Garcia (FRA)
Head-to-head: Garcia leads 2-0 (including 1-0 on outdoor hard courts)
This will be the third time that Garcia and Cirstea have played -- all at WTA 1000 level. Garcia won both of the previous two encounters in three sets, at Toronto 2017 and Madrid 2019.
This is the fourth time that Garcia has made the fourth round in Indian Wells, following 2015, 2017 and 2018. But she will be bidding for a quarterfinal debut here, as well as her fifth tour-level quarterfinal of 2023.
Cirstea played her first Indian Wells main draw in 2009 as the No.32 seed, losing her opener to Elena Vesnina. But she did not get beyond the third round until last year. Now she has made the last 16 twice in a row.
Marketa Vondrousova (CZE) vs. Karolina Muchova (CZE)
Head-to-head: Vondrousova leads 2-0 (0-0 on outdoor hard courts)
The only fourth-round match between unseeded players is one that pits two former Top 20 players who have been beset by injury against each other. Muchova is making her Indian Wells debut, while Vondrousova is in the last 16 here for the fourth time in five appearances.
Vondrousova took out Simona Halep to make her WTA 1000 quarterfinal debut here in 2019. A victory against Muchova would put her in the last eight of a WTA 1000 event for the first time since Rome 2020.
This will be the first time Vondrousova and Muchova have played each other at tour level. Vondrousova's two wins came in the 2017 Prague ITF W80 final and in 2018 Stuttgart qualifying.
 Elena Rybakina (KAZ) vs. [Q] Varvara Gracheva
Head-to-head: Rybakina leads 1-0
Rybakina is bidding to make the last eight of Indian Wells for the second year running. A win today would mean Indian Wells is the first tournament at a WTA 1000 level or above at which the Kazakh has reached multiple quarterfinals.
Gracheva, who reached her first WTA final in Austin two weeks ago, has now won nine of her past 10 matches. The World No.66 opened her Indian Wells qualifying campaign only two days after the Austin final. She needed 3 hours and 20 minutes to edge Anna-Lena Friedsam 7-6(5), 6-7(6), 6-4 in the final qualifying round. However, Gracheva has yet to drop a set in the main draw, including wins against No.25 seed Petra Martic (against whom she had been 0-5) and No.8 seed Daria Kasatkina (reprising her upset of Kasatkina in the first round of the Australian Open).
 Maria Sakkari (GRE) vs.  Karolina Pliskova (CZE)
Head-to-head: Pliskova leads 3-2 (including 2-1 on outdoor hard courts and 1-0 in 2023)
Pliskova made her comeback from a hand injury exactly 12 months ago at Indian Wells 2022, losing her opener to Danka Kovinic and fell out of the Top 30 by the end of the year. But she has now returned to the Top 20 after making the quarterfinals of three of the last four events at WTA 1000 level or above. She will bid to make it four out of the last five against Sakkari.
Since her return, Pliskova owns two wins over Top 10 players -- both against Sakkari, at Toronto 2022 and a 6-1, 6-2 rout in Dubai last month.
Sakkari, last year's runner-up, has reached this stage after two victories from a set down against opponents she had never previously beaten, Shelby Rogers and Anhelina Kalinina.
 Petra Kvitova (CZE) vs.  Jessica Pegula (USA)
Head-to-head: Kvitova leads 3-1 (all on outdoor hard courts; Kvitova leads 1-0 in 2023)
Pegula is bidding to reach a seventh consecutive quarterfinal at WTA 1000 level and above. She has made at least that stage of eight of the past 10 such tournaments dating back to Miami last year. The American has previously made the Indian Wells quarterfinals once, in 2021.
Kvitova has made the last 16 in Indian Wells for the first time since her 2016 quarterfinal run and for just the fourth time in 12 appearances. She defeated Pegula 7-6(6), 6-4 in United Cup group stage action at the start of the 2023 season.
 Coco Gauff (USA) vs. [Q] Rebecca Peterson (SWE)
Head-to-head: Peterson leads 1-0
Peterson's previous win over Gauff came in the second round of the 2019 Midland ITF W100 event. Gauff was 14 years old and ranked No.684. It was the fifth professional tournament of her career.
Gauff owns a 13-3 record this year and is bidding for a fourth quarterfinal in five events. Peterson owns a 15-3 record this year and has progressed beyond the third round at WTA 1000 level or above for the first time.
Peterson is seeking a third career Top 10 win following her defeats of Sloane Stephens at Washington 2019 and Aryna Sabalenka at Adelaide 2022.
 Barbora Krejcikova (CZE) vs.  Aryna Sabalenka
Head-to-head: Sabalenka leads 2-1 (1-1 on outdoor hard courts; Krejcikova leads 1-0 in 2023)
Krejcikova pulled off a 0-6, 7-6(2), 6-1 comeback over Sabalenka in the Dubai quarterfinals, having trailed 6-0, 3-1. That result snapped Australian Open champion Sabalenka's 13-match winning streak.
Sabalenka is bidding to reach the last eight of Indian Wells for the first time. It is the only WTA 1000 event (aside from last year's inaugural Guadalajara) at which she is yet to make the quarterfinals. Her previous best showing was the fourth round in 2019. Krejcikova also made the fourth round on her only previous appearance here in 2021.