(BBC) – Venus Williams and Leylah Fernandez claimed a shock victory over reigning champion Lyudmyla Kichenok and her partner Ellen Perez in the first round of the US Open women’s doubles.

Williams, 45, and Fernandez, 22, ground out a 7-6 (7-4) 6-3 win against the sixth seeds to progress to the second round, where they will face Japan’s Eri Hozumi and Ulrikke Eikeri of Norway.

Williams, a 14-time Grand Slam doubles champion, only accepted a wildcard invitation to partner Fernandez on Wednesday, and they soon looked set for an early exit.

They trailed 5-2 in the first set after losing two break points, but fought back with two breaks of their own before winning the set tie-breaker.

The energy of that comeback carried over into the second set as the American and Canadian duo broke to love in the second game before saving two break points when under pressure in the third.

The set went with serve until the end when Fernandez – who was born three years after Williams won her first New York women’s doubles title in 1999 – served to love to secure victory.

Ukraine’s Kichenok won the women’s doubles title last year alongside Jelena Ostapenko.

“We came in and tried to figure things out in the beginning,” Fernandez said.

“Venus said the most amazing, amazing strategy during a changeover: bring your energy up. That definitely helped.

“It was nerve-wracking, exciting,” Fernandez said of playing alongside her tennis idol Williams.

“The night before I was shaking, I was super happy. You were super nice and welcoming, that brought my nerves down, so thank you for doing that!”

On her partner, Williams said: “We play the same style, I’m just a little bit bigger, but we’re a great team. She’s the best partner I’ve had outside of Serena.”

Williams was also given a wildcard to compete in the women’s singles, and put in an impressive performance against 11th seed Karolina Muchova earlier this week before eventually losing in a deciding set.

She won the US Open women’s doubles title in 1999 and 2009 alongside younger sister Serena.

Fernandez, who lost to Great Britain’s Emma Raducanu in the 2021 US Open final, is the 31st seed in the singles draw and will play world number one Aryna Sabalenka in round three on Friday.