ROME, Italy -- Johanna Konta of Great Britain emerged victorious after a three-set tussle in the second round of the Internazionali BNL d’Italia on Thursday, with a 6-7(5), 6-4, 6-1 upset of No.7 seed Sloane Stephens of the United States.

"Today the sun is shining, the sky is blue," Konta told the press, following her win in a match postponed from Wednesday. "It was nice to get out there and have a really tough, competitive match against Sloane. I was very happy I was able to come through and play another match today."

Read more: Rome 2019: Thursday's Order of Play and Weather Update

World No.42 Konta squandered a 4-0 lead in the opening set, but rebounded from losing that set in the tiebreak to grind through the final two sets and move into the round of 16 at Rome for the fourth consecutive year, after two and a half hours of fascinating play.

"I definitely raced ahead in the first set," said Konta. "However, Sloane is as successful as she is because she does find a way to raise her level. She did that. I was very pleased how I was able to continue competing, see the good things I was doing, because there were plenty of them. Just trusted in being able to accumulate enough points to create chances."

Konta picked up her second Top 10 win of the year, both of which came over Stephens, as she tries to regain the form that pushed her into the Top 5 in 2017. Konta also defeated Stephens in straight sets in the first round of Brisbane this year, and now holds a 2-0 head-to-head lead over the 8th-ranked American.

There will be no rest for the weary as Konta, like many other players, will contest a second match later on Thursday. However, Konta’s next opponent, former World No.1 Venus Williams, had already moved into the third round on Tuesday. Williams was slated to face her sister Serena in the second round before Serena withdrew from the event due to a knee injury.

Venus Williams leads the head-to-head with Konta by 4-3, and one of Williams's wins came in the round of 16 at Rome in 2017.

"I mean, that's exciting," Konta said. "I've played [Venus] once before here, on the same court. It will be nice to share the court with her again. I always enjoy playing her. She's someone who's left and is leaving such a mark on our sport. I'm just looking forward to playing against her again."

The first set started with Konta firing winners from all sectors of the court, while Stephens struggled with miscues, giving the Brit an early break. After staving off four break points to hold for 3-0, Konta broke Stephens again after the American shot an unforced error into the net, and a visibly frustrated Stephens faced a dire 4-0 deficit.

But from there, Stephens picked up her game, getting on the board by claiming one service break back with a backhand crosscourt winner. The American utilized deep returns to flummox Konta into giving up another break, and Stephens was suddenly back on serve at 4-3.

Stephens continued her strong fightback by using glorious groundstrokes to break Konta at love for a 6-5 lead. However, serving for the set, the seventh seed faltered, and she hit consecutive backhand errors to end the final two points of the game, forcing a first-set tiebreak.

Errors from the Brit set Stephens up with a 5-2 lead in the breaker, and another long backhand from Konta gave the American triple set point at 6-3. Stephens slammed a forehand winner on her first opportunity to close out the set, polishing off a marvelous comeback from 0-4 down.

Konta wrested momentum away from Stephens early in the second set, taking the initial lead at 3-2 after Stephens double faulted on break point. Konta, though, dropped serve in the next game, blasting a backhand error long to put the set back level at 3-3.

But that was Konta’s only misstep in that set as her serving strength improved, and she attained a crucial break at 4-4 with an error-forcing crosscourt backhand on break point. Serving for the set at 5-4, Konta stayed aggressive with big serves, and forced an error with a forehand on her second set point to level the match at one set apiece.

Stephens held to open the deciding set but from that juncture forward, Konta took command of the match by winning numerous close games on the American’s service. Stephens could not convert any of her six game points at 1-1, and finally dropped that game with back-to-back errors, ceding a pivotal break to the Brit.

The American again dropped serve to fall behind 4-1, squandering two game points there, and Konta followed by holding with relative ease for 5-1. In the next game, Stephens again let a 40-15 lead slip, and a forehand pass by Konta at deuce gave the unseeded player match point. There, the British No.1 forced an error with a sound backhand return, wrapping up a six-game winning streak to clinch the victory.