If you were a Serena Williams fan, it all looked so reassuring again on Thursday night as she pounded first serves and ripped winners on the run against an overwhelmed younger opponent to reach her 10th United States Open final in style.

But the tricky part for Williams in this latest and perhaps most fascinating phase of her long, layer-cake of a career has not been bringing the thunder in matches like Thursday’s 6-3, 6-1 semifinal defeat of Elina Svitolina.

It has been Saturdays with Grand Slam titles on the line.

Williams was once virtually rock solid with major hardware at stake, but lately she has lost her ability to close.

She won 21 of her first 25 Grand Slam finals but has lost five of her last seven and has lost all three she has played since returning to the game last year after the birth of a daughter, Olympia, in September 2017.