Former world No 1 Maria Sharapova battled back Wednesday to reach the third round of the US Open while next-generation rising stars Alexander Zverev and Nick Kyrgios crashed out.

Sharapova, who downed second-ranked Simona Halep in her first Grand Slam match after a 15-month doping ban, defeated Hungary’s 59th-ranked Timea Babos 6-7(4), 6-4, 6-1 at Arthur Ashe Stadium.

“I felt like going into the match I just wanted to get it done,” Sharapova said.

“It wasn’t my best tennis. It was scrappy tennis but sometimes those kind of matches are a lot of fun and this was one of those days.”

The 30-year-old Russian became the first player into the third round where she will face Russian-born US teen wildcard Sofia Kenin.

Sharapova, whose five Grand Slam titles include the 2006 US Open, tested positive for meldonium at the 2016 Australian Open, her most recent Grand Slam appearance until this week.

“Every day I have the chance I have to play out here at the US Open is a special day and I’ll look forward to the next one,” Sharapova said.

Sharapova, ranked 146th, played only one Open tuneup match due to a forearm injury but wore down Halep and Babos to prove she’s a threat for a deep run.

Zverev stunned

German fourth seed Zverev, whose five ATP titles this year include a win over Roger Federer in this month’s Montreal final, fell to 61st-ranked Croatian Borna Coric 3-6, 7-5, 7-6(1), 7-6(4).

“He had a most unbelievable year where he won basically everything,” Coric said. “It does mean a lot to me to win this match.”

Coric, who next faces South African Kevin Anderson for a spot in the last 16, was one point from being pushed to a fifth set before winning five in a row to take the 12th game of the final set.

“I was just thinking to keep the points shorter,” Coric said. “And yeah, I was a little bit lucky.”

Zverev’s ouster left US 10th seed John Isner the top-ranked player in his draw quarter and Croatian fifth seed Marin Cilic, coming off a Wimbledon runner-up effort, the best in his half of the draw.

Cilic, the 2014 US Open winner, reached the third round by beating Germany’s Florian Mayer 6-3, 6-3, 6-3.

Kuznetsova, Venus win

Russian eighth seed Svetlana Kuznetsova, the 2004 US Open champion, rescued three match points in defeating 67th-ranked Czech Marketa Vondrousova 4-6, 6-4, 7-6(2) to reach the second round.

Kuznetsova is among seven women who could become world No 1 after the US Open. So is Ukraine’s fourth-seeded Elina Svitolina, who held off 42nd-ranked Czech Katerina Siniakova 6-0, 6-7(5), 6-3.

Also sustaining top spot hopes was seven-time Grand Slam champion Venus Williams, the US ninth seed who beat France’s Oceane Dodin 7-5, 6-4. This year’s Wimbledon and Australian Open runner-up is the field’s oldest woman at 37.