Sinner, Alcaraz survive US Open wobbles

Jannik Sinner and Carlos Alcaraz survived US Open first round wobbles on Tuesday to stay on course for a semifinal showdown.

World number one Sinner fought back from a set and break down to defeat 140th-ranked Mackenzie McDonald in his first match since being embroiled in a doping test controversy.

Alcaraz, the third seed and 2022 champion in New York, overcame a second set blip to defeat 186th-ranked qualifier Li Tu of Australia 6-2, 4-6, 6-3, 6-1.

Italian Sinner battled to a 2-6, 6-2, 6-1, 6-2 win over American opponent McDonald on Arthur Ashe Stadium, racing away with 18 of the last 22 games.

The 23-year-old was returning to action just a week after it was revealed he had failed two drug tests in March.

However, he escaped a lengthy ban when officials decided he wasn't at fault for the presence of banned anabolic agent clostebol in his system.

"The response from fans, I feel it has been great, also throughout when the news came out, in the practice sessions, there was a lot of support," said Sinner.

"It's still a little bit not easy. You have to go through day by day."

Alcaraz, who won the first of his four Grand Slam titles in New York in 2022, opened the night session against Tu who hasn't won a match on the main tour this year.

However, Tu thrilled the crowd as he went about his task of facing a player who is attempting to become only the third man in the modern era to win the French Open, Wimbledon and US Open in the same year.

After being outplayed in the opening set, Tu levelled the tie on a fifth set point in the second.

But Alcaraz crushed any hint of a shock result by running away with the clash to record his 15th successive Grand Slam match win.

"He surprised me a little bit. In the first set, he was nervous but after that he grew into it and played great tennis," said the Spanish star.

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