CHARLESTON, SC, USA -- No.8 seed Madison Keys of the United States moved into the third round of the Volvo Car Open on Wednesday after a grueling 7-6(5), 4-6, 6-4 victory over Germany's Tatjana Maria.

18th-ranked Keys, who reached the Charleston final in 2015 before falling to Angelique Kerber in the championship match, came back from a late break down in the final set, extending her head-to-head record against World No.59 Maria to 3-0 following her nearly two-and-a-half-hour win.

Photos: Charleston champions: From Lisicki to Bertens

The 24-year-old American was two points away from a 7-6, 5-1 lead in the match before Maria came roaring back to force a third set. Keys ended up with the win after blasting 50 winners versus 42 unforced errors during the encounter. Maria had more aces than Keys by five to two, and each player broke the other three times on the evening.

Keys will now take on No.10 seed Jelena Ostapenko of Latvia in a third-round battle of former Charleston finalists. Ostapenko, who lost to Daria Kasatkina in the 2017 Volvo Car Open final, squeaked past hometown favorite Shelby Rogers earlier on Wednesday.

The match started with Maria having to save break points in both of her first two service games, while Keys was cruising on serve, dropping only two points in her first three service games. Eventually, though, Maria found herself untroubled on her deliveries, while Keys ran into a few dicier games when she stepped to the line.

That pattern reached its apex in Keys’s service game at 6-5, when outstanding defense by Maria extended a rally to the point where Keys fired an overhead long, bringing up set point for the German. But Keys hit a winning volley to pull back to deuce, and would go on to close out the game with a dropshot winner.

With no breaks of serve in the opener, the players advanced to the tiebreak. A Keys double fault gave Maria an early minibreak, but the American pulled through rallies to level at 3-3. Maria hit a forehand pass down the line to keep her in the mix at 5-5, but the next two points ended with blazing winners by Keys, clinching the one-set lead for the American.

Keys claimed the first break of the second set to lead 2-0, after a Maria forehand error on the American’s fourth break point of the game. Keys fended off a break point in her next service game, eventually holding and maintaining her break through 4-1. In that game, Keys had two break points to take a 5-1 lead, but Maria held on for 4-2.

The set completely turned around from there. Keys dropped serve at love, with Maria finding herself back at 4-3. The German then fought through a protracted game on Keys’s serve at 4-4, using excellent placement on her shots and taking advantage of late errors by the American to clinch a fourth straight game and a 5-4, single-break lead.

Serving for the set, Maria found herself down double set point, but backhand errors by Keys allowed Maria back to deuce. The German reached set point after a strong serve was returned long by Keys, and Maria converted her chance when she ended a rally with a well-timed lob for a winner.

After losing five straight games, Keys did well to hold her serve to open the final set and post another game to the scoreboard. But Maria was zooming through her service games at this point, holding for 3-3 at love with incredible zest on her delivery.

The German earned the first break of the decider in the following game, as an increasingly frustrated Keys dropped serve with a double fault. However, with the lead in hand, Maria squandered a 30-0 start in the subsequent game, dropping serve with a long forehand error, and visibly dismayed as she found herself back level, at 4-4.

The Keys resurgence lasted for the remainder of the match. A quick hold for 5-4 was succeeded by a clutch of fierce forehands from the American in the next game, to get to match point. There, a scintillating rally was broken open by a surprising drop shot by Keys, which Maria was unable to track down, sealing the victory for the No.8 seed.

More to follow....