Stephens returned to NY with a spring in her step amid hopes of becoming the first woman to retain a Grand Slam title since Serena Williams triumphed at Wimbledon in 2015 and 2016. When you're playing a whole new draw, different seedings, different ranking, there's so much that goes into it.
"I think just like I always say, get your racket on it, make a play on the ball, make your opponent play an extra ball", Stephens told reporters. "It was important that I won the first set".
The 28-year-old Sevastova, who avenged last year's quarter-final loss to Stephens in NY to reach her first Grand Slam semi-final, converted five of her eight break points and saved seven of the nine against her.
In the seventh game Mertens balky forehand came undone.
She broke again to go up 2-0 in the second set before Stephens, pleading with herself to fight, broke back. "I think she lost also her nerves a little bit, it's normal". On account of a Stevens sixteen winners, one double and 25 unforced errors, and carried out 4 break factors out of eight.
But she trailed by a break in the opening set, and then was a point from being behind 4-1, before turning things around. Stephens has dropped just a single set so far during her time at the US Open. The momentum didn't quite carry over.
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However, his £100 million move to the Old Lady seems to have made Juve favourites to win the European elite club competition. Barcelona and Argentina forward Messi had featured in the top three for 11 straight years.
Having reached her second Grand Slam final at this year's French Open before an encouraging tune-up to Flushing Meadows, Stephens was considered a favourite. "I can win it maybe next week again".
Karolina Pliskova defeated Ashleigh Barty, 6-4, 6-4, to book a spot in the quarterfinals against Serena Williams. So I'm not going to dwell on it.
Throughout the match Stephens complained about the heat and there were some questions as to whether or not the players should have stayed on.
It hasn't been an outstanding season for Pliskova, who has one tournament victory, but a positive outlook carries her forward. She received a wild card into last year's U.S. Open and became the youngest player ever to make the girls' final. "So that's why I win a lot of those matches which are not great, not easy".
Certainly was. And that chase-down, tunaround, hook-shot of a passing victor just showed a glimpse of how the No. 3 can go from defense to offense with flair, as she did repeatedly during her 6-3, 6-3 victory over No. 15 Elise Mertens of Belgium in the fourth round.