Former champion Madison Keys led a successful day session for Americans at the Credit One Charleston Open on Tuesday. The No.9 seed eased to a 6-4, 6-3 win over wildcard Emma Navarro in Tuesday's first round.

One of five all-American matches on the docket in the opening round of the WTA 500 event, the more experienced Keys needed just 1 hour and 15 minutes to knock off former University of Virginia star Navarro, the 2021 NCAA collegiate singles champion.

Keys hit 29 winners, including seven aces, and broke serve four times to improve to 18-8 in Charleston all time. 

"I absolutely love playing here; I can't believe I've been here every single year for 10 years straight now," Keys said afterwards. "I am so happy to be back. I love coming here; the fan support's amazing, and the entire tournament, everyone who's involved, are some of my favorite people in the world, so it's always a stop on my schedule."

How the match was won: Keys won the first four games of the opening set, and later held on to the lead after breaking to open the second set. Navarro pulled closer from 5-1 down in the first set, but never could draw level after falling behind early. 

A crucial moment came in the sixth game of the second set; Navarro had three break points to level the set at 3-3, but couldn't find the equalizer. 

Afterwards, Keys was full of praise for the effort of her younger compatriot. 

"I think Emma is an amazing player," she said. "I definitely knew it was going to be a tough match; she always plays really well here in front of a home crowd. I knew I was going to have to play some good tennis; she definitely made it tricky and made me level up a couple of times. I think she has a very bright future in front of her."

Keys was one of seven Americans to win in the day session, along with Hailey Baptiste, Caroline Dolehide, Sofia Kenin, Caty McNally, Bernarda Pera and Shelby Rogers.

Local favorite Rogers downs Collins in all-American affair; Kenin finishes off Sasnovich in rain-delayed opener

The highest-profile all-American affair of the five came as day turned to evening, and saw Charleston native Shelby Rogers rally for a 6-7(2), 6-4, 6-1 win over No.13 seed Danielle Collins. 

A quarterfinalist at her home tournament in 2017, the 2 hour, 11-minute win is Rogers' first in her hometown since 2019. After losing six straight points in the tiebreak to drop the first set, Rogers gamely rebounded for her third straight win against Collins. She broke Collins four times in the second and third sets, and won eight of the last nine games in all. 

"She was painting every line out here," Rogers said afterwards. "I knew it was going to be really tough. She can just turn it on at any moment, so I knew once I got ahead in the third, I really had to stay with it.

"It never gets old, playing here every time. I've got chills right now ... and I'm really happy I could get it done today."

Highlights: Rogers def. Collins | Kenin def. Sasnovich

Elsewhere, both Dolehide and Kenin came back to win after being pushed off the schedule on Monday night due to rain; while Dolehide and Sabine Lisicki never took the court on Monday night, Kenin's Round 1 match against Aliaksandra Sasnovich was suspended with the 2020 Australian Open champion leading 6-1, 6-7(5), 3-0. 

Kenin ultimately finished off Sasnovich after Keys' victory on Credit One Stadium, 6-1, 6-7(5), 6-1, while Dolehide was a 6-4, 6-4 winner over 2009 Charleston winner Lisicki on Court 3.