The only two former champions in the 2021 Volvo Car Open draw will clash as early as the second round after Sloane Stephens defeated lucky loser Wang Xinyu 6-2, 7-5 in her opener.

The result sets up a meeting between the 2016 winner and No.8 seed Madison Keys, who captured the Charleston title in 2019. That run featured Keys' first win over Stephens in four meetings 7-6(6), 4-6, 6-2 in the quarterfinals.

Stephens' first-round contest with Wang did not heat up until the second set, but once the Chinese 19-year-old found her range delivered a knife-edge finish. Wang, who had lost to Gabriela Talaba in the final round of qualifying and was playing her first WTA main draw match on clay, looked every inch the terre battue novice to start with. Impatient rallying and 12 unforced errors saw her drop the first set in a flash.

Although Wang's was able to sustain longer rallies as the level improved in the second set, Stephens was still too solid from the back of the court. The former US Open champion, now ranked World No.57, nailed a forehand pass to break Wang for 3-2 and nabbed an insurance break as well to lead 5-2.

It was only with her back to the wall that Wang began to play her best. Suddenly hitting cleanly and rattling off rapid-fire winners, she began to dominate from all corners of the court. The two-time junior Grand Slam doubles champion's decision to come forward also paid off, garnering her seven of nine net points.

With Stephens serving for the match for a second time at 5-4, Wang would stave off three match points - two with searing forehand winners - and hold a break point to level the score. But with the momentum finely poised, Stephens played her own best point of the match, finding a backhand winner after an extended rally, and minutes later sealed victory with a timely first ace.

Shelby Rogers held off Kristina Mladenovic in the first round of the 2021 Volvo Car Open.

Photo by Volvo Car Open/Chris Smith

Earlier, Charleston native Shelby Rogers excelled on home soil once again with a 6-4, 6-3 win over Kristina Mladenovic. Rogers, whose best performance here to date was a quarterfinal showing in 2017, struck 22 winners to 14 unforced errors and was broken just once. She will next face No.13 seed Amanda Anisimova in an all-American derby.

Mladenovic saved her best tennis for the end of each set, forcing Rogers to battle to close both out but was ultimately undone by 13 double faults. They often piled up at unfortunate times for the Frenchwoman. Having prevented Rogers from serving out the first set, three paved the way to immediately losing it on her own serve anyway. A further two enabled Rogers to take swift control of the second set, leading to what would prove to be the decisive break in its second game.

Leylah Fernandez upset No.16 seed Zhang Shuai in the first round of the 2021 Volvo Car Open.

Photo by Volvo Car Open/Chris Smith

Elsewhere, Monterrey champion Leylah Fernandez continued her good form with a 6-3, 6-1 defeat of No.16 seed Zhang Shuai. So too did resurgent Miami quarterfinalist Anastasija Sevastova, who progressed past Anastasia Potapova 6-3, 6-3. No.12 seed Ons Jabeur delivered Tuesday's first seeded win, dismissing Martina Trevisan 6-2, 6-2.

There was also a notable WTA main draw debut for Texas Tech alumna Gabriela Talaba. The Romanian qualifier, a left-hander with a single-handed backhand and a stylish array of spins in her repertoire, impressed in a tight first-round contest before falling 7-6(2), 6-4 to Danka Kovinic.

2021 Charleston 500 Highlights: Stephens holds off Wang Xinyu fightback

2021 Charleston 500