No.6 seed Coco Gauff started her 2023 Miami Open campaign with a 6-4, 6-3 second-round victory over Rebecca Marino on Stadium Court on Thursday.

Gauff, who resides in Southeast Florida, took 1 hour and 12 minutes to pick up victory at her local Hologic WTA Tour event and reach the third round for the second straight season. Last year she went one step further into the Round of 16, her career-best Miami Open showing.

"Today it was an up-and-down match, honestly," Gauff said afterwards. "I did well in the returning part, considering [Marino is] a big server. I'm really happy with how I played.

"She's not an easy opponent. She makes a lot of big shots, doesn't really give you a lot of rhythm. You kind of just have to hang in there."

Fast facts: Gauff, who turned 19 last week, now holds the record for most match-wins at WTA 1000 events before turning 20, with her 34th at this level coming over Marino. She breaks a stalemate with Anastasia Pavlyuchenkova, who collected 33 WTA 1000 match-wins before she turned 20.

On Thursday, Gauff picked up her second win in two meetings with Canada's Marino, converting five of her nine break points and twice coming back from a break down in the second set. Gauff also defeated Marino en route to her first Grand Slam singles final at Roland Garros last year.

Marino was again denied her first Top 10 win, in her tenth career meeting against Top 10 opposition. Marino nearly picked up a Top 10 win last season, pushing both Maria Sakkari and Caroline Garcia to three sets in 2022.

Key moments: Gauff saw an early break in the first set slip away when Marino slammed back-to-back forehand winners to pull back on serve at 4-3. But the American teen was unfazed, firing her sixth ace of the set to hold for 5-4, then breaking Marino for the second time to claim the opener.

In the second set, Gauff fought back from a break down at both 2-1 and 3-2, then took charge for good by forcing an error with a deep service return to lead 5-3.

Marino grabbed a break point in the following game, but Gauff leveled up, slamming three strong serves in a row, each returned into the net, to close out the victory.

Next up: Gauff will next face No.27 seed Anastasia Potapova in the third round. Gauff defeated Potapova in a tough three-setter at the 2019 US Open, and she also advanced past Potapova at 2021 Montreal when Potapova retired while trailing 5-0.