MONTERREY, Mexico -  Former World No.3 Sloane Stephens overcame a tough challenge from American wildcard Emma Navarro to advance, 6-4, 5-7, 6-1 and reach the Abierto GNP Seguros second round.

Seeded No.5, Stephens came to Monterrey as a wildcard in search of a first match win of the season, and her experience helped her snap a five-match losing streak for a victory over her 18-year-old countrywoman after two hours and 16 minutes on Estadio GNP Seguros.

"It was a tough match," assessed Stephens afterwards. "It's tough when you don't know an opponent that well, you're still getting used to how they play as you're going, and even tougher to play against an American. Happy to get my first win of the season here, hopefully more to come."

A former US Open champion and Roland Garros runner-up, Stephens has struggled to find that same level since reaching the 2018 WTA Finals final in Singapore, winning back-to-back matches just once after Wimbledon. Navarro impressed last year on the junior circuit, reaching the French Open girl's final (winning the doubles) and Wimbledon girl's semifinals, making her WTA main draw debut at the Volvo Car Open last spring.

The pair exchanged breaks to start but it was Stephens who was soon on the ascendency, breaking serve in the fifth game and holding on for the set without facing another break point.

Taking that momentum into the second set, Stephens was soon up 2-0 with three chances for a double break lead. Navarro steadied and began to come alive, showing all her mettle to remain on serve in the face of nine break points in her next three service games.

One game from a deciding set, Stephens found herself on the back foot as Navarro engineered a pair of set points, forcing an overhead into the net to level the match.

Stephens nonetheless began the final set as she began the second, taking a 2-0 lead with chances for another double break; this time she makes no mistake on her third opportunity, moving within three games of victory with a thunderous backhand winner.

Despite the subsequent 1-5 deficit, Navarro made one last stand as she gamely saved two match points, but couldn't save the third as Stephens secured her first victory of the season.

When asked for the key to pulling through long three-setters, Stephens responded: "Do your best, keep fighting 'til the end, try to make something happen."

Up next for the American is either Abierto Mexicano Telcel runner-up and rising Canadian star Leylah Annie Fernandez or Swiss qualifier Stefanie Voegele, who has won her last four matches against Stephens - most recently at the 2019 BNP Paribas Open, where she lost just three games.

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