体坛英语资讯：Latvian Sevastova stuns defending champ Stephens in U.S. Open quarters

NEW YORK, Sept. 4 -- The 19th seed Anastasija Sevastova from Latvia stunned defending champion Sloane Stephens from the United States 6-2, 6-3 in the U.S. Open women's singles quarterfinals here on Tuesday.

Stephens had beaten Sevastova in the same round last year en route to her first Grand Slam title. But her serve was the bigger problem today as the third seed was broken five times in the 84-minute match.

Sevastova advanced to the first major semifinal of her career and will play either Serena Williams or 2016 U.S. Open runner-up Karolina Pliskova in the semis.

The match was played when the temperature pushed above 32 degrees Celsius, prompting tournament officials to implement the extreme heat policy, which has been in effect for most of the tournament.

"It was very physical today. It's so hot in here," the 28-year-old Sevastova said. "It was important that I won the first set."