Canadian teenager Denis Shapovalov cruised into the second round of the U.S. Open with a 7-5, 6-1, 6-2 win over Russia's Daniil Medvedev on Monday, his first victory in a Grand Slam event.

Shapovalov, from Richmond Hill, Ont., won the match in one hour 36 minutes to continue his impressive summer that saw him reach the semifinals of the Rogers Cup in Montreal.

Shapovalov converted his seventh break point to take a 5-2 lead in the third set. Serving for the match, Shapovalov converted on his first match point opportunity by firing his sixth ace of the match past Medvedev.

The Canadian teenager has had an August for the ages, which included seeing his world ranking jump to 67th. 0:40

The 18-year-old left-hander committed just two double-faults to Medvedev's eight, and won points on 72 per cent of his first serves.

Shapovalov, playing in his first U.S. Open, next faces eighth seed Jo-Wilfried Tsonga of France.

Sharapova shines in return

So much about Maria Sharapova was the same as it ever was during her first Grand Slam match since a 15-month doping suspension: the shot-punctuating shrieks, the aggressive baseline style, the terrific returning, the sometimes-shaky serving.

Another familiar sight: The five-time major champion gutted out a victory.

Sharapova recovered after faltering midway through the match and emerged to beat No. 2-seeded Simona Halep 6-4, 4-6, 6-3 to reach the second round.

"This girl has a lot of grit and she's not going anywhere," Sharapova told the crowd in an on-court interview.

Maria Sharapova advances to 2nd round with 6-4, 4-6, 6-3 victory over Simona Halep. 1:43

After leading by a set and 4-1 in the second, Sharapova showed some fatigue and rust, dropping five games in a row. But in the third, Sharapova regained control by going ahead 3-0, using her power to keep two-time French Open runner-up Halep under pressure.

Sharapova had not played at a Grand Slam tournament since January 2016, when she tested positive for the newly banned heart drug meldonium during the Australian Open. It was as if every one of Sharapova's winners — and she compiled 60, 45 more than Halep — was her way of declaring, "I'm back!"

The 30-year-old Russian was allowed back on the tour this April, but she was denied a wild-card invitation for the French Open the next month. The U.S. Tennis Association did grant a wild card to Sharapova, who was once ranked No. 1 but is currently 146th.

Konta stunned in opening round

Seventh-seeded Johanna Konta lost in the first round of the U.S. Open, stunned by 78th-ranked Serbian Aleksandra Krunic 4-6, 6-3, 6-4.

Konta was a semifinalist at Wimbledon last month and was one of eight women who had a shot at the No. 1 ranking going into Flushing Meadows.

Konta had been considered Britain's greatest hope to win a U.S. Open title after Andy Murray pulled out with a hip injury just days before the event.

Garbine Muguruza began her U.S. Open with an easy victory, looking like a favourite whether she believes it or not.

The Wimbledon champion, who has never been past the second round here, beat Varvara Lepchenko of the U.S. 6-0, 6-3 in just over an hour.

No. 5 Marin Cilic followed her onto Arthur Ashe Stadium and beat American Tennys Sandgren 6-4, 6-3, 3-6, 6-3 in his first match since the Wimbledon final, hoping he's healthy enough to make a run through a men's field that's been decimated by injuries.

Williams shakes off lapse to advance

Venus Williams shook off a mid-match lapse to improve to 19-0 in the U.S. Open's first round and stay in the hunt for the No. 1 ranking.

The No. 9-seeded Williams, at 37 the oldest woman in the field, picked up a 6-3, 3-6, 6-2 victory over Viktoria Kuzmova, a 19-year-old qualifier from Slovakia who is ranked 135th.

Williams entered the U.S. Open as one of eight women with a chance to rise atop the WTA rankings by tournament's end.

Venus Williams takes her opening match at the U.S. Open against Viktoria Kuzmova, winning 6-3, 3-6, 6-2 1:36

It was the first tour-level main draw match of Kuzmova's career, the 967th for Williams, who won the title at Flushing Meadows in 2000 and 2001.

Williams was up a set, plus a break in the second at 2-0, when she faltered. Kuzmova broke for 2-1, then pulled at even at 3-all before taking three games in a row to force a third set. But Williams righted herself there, breaking for a 2-0 lead, then digging out of a love-40 hole for 3-0.

Haase falls early

On the men's side, No. 21 David Ferrer of Spain was beaten by qualifier Mikhail Kukushkin of Kazakhstan, 4-6, 6-3, 6-2, 6-1. No. 32 Robin Haase of the Netherlands was the other seeded player to fall early.

Moving on along with Cilic were No. 8 Jo-Wilfried Tsonga of France, No. 12 Pablo Carreno Busta of Spain and No. 28 Kevin Anderson of South Africa.

Women's winners included No. 13 Petra Kvitova of the Czech Republic, No. 18 Caroline Garcia of France, No. 31 Magdalena Rybarikova of Slovakia, and No. 30 Julia Goerges of Germany.

Women's seeded losers included No. 24 Kiki Bertens of the Netherlands and No. 32 Lauren Davis of the U.S.