NEW YORK (AP) Maybe Serena Williams simply wanted to put on a better show for her pal Beyonce.
Looking rather displeased with herself at times, including when she shook her head and smirked on the way to the net for a post-victory handshake Thursday night, Williams still managed to tie Martina Navratilova's professional-era women's record with her 306th career victory in Grand Slam matches.
Williams beat Vania King 6-3, 6-3 to reach the U.S. Open's third round.
''I just think it should have been a different scoreline for me. I feel like I made a lot of errors,'' Williams said. ''But, you know, there's nothing I can do about that now. What really matters is I got the win. Hopefully I'll just get better.''
Really? This performance didn't seem OK? After all, Williams delivered 13 aces with serves that reached 121 mph. She compiled a 38-4 edge in winners. She only dropped six games and needed all of 65 minutes to win.
''I just didn't have a great day,'' was her assessment.
Yes, there were problems. The 28 unforced errors The return game: She won only 13 of 40 points on King's first serves. Williams did, however, smack one backhand return winner in the final game.
Music power couple Beyonce and Jay Z sat behind Williams' coach, Patrick Mouratoglou, in the player's guest box Thursday.
''It's always good,'' Williams said casually, ''to have Beyonce and Jay in the box.''
King noticed Williams' negative body language as she headed to the net.
''I think Serena's a perfectionist. She always wants to play her best. ... If she doesn't play really well, she's always a little bit hard on herself,'' King said.
Delivering 13 aces with the roof closed at Arthur Ashe Stadium, and showing no signs of a sore right shoulder that she said requires ''constant'' treatment, Williams improved to 306-42 in matches at major tournaments, a winning percentage of .879. Navratilova retired with a 306-49 mark.
Only Roger Federer, with 307, has won more Grand Slam matches than Williams in the Open era, which dates to 1968 - and he won't add to that total during this tournament because he is out for the season as he rehabs his surgically repaired left knee. Williams can equal Federer's total by beating 47th-ranked Johanna Larsson of Sweden on Saturday.
''Would like to take one more step,'' Williams said while discussing her Slam win total. After a pause, she added: ''several more steps.''
That's because it'll take five more victories to win the championship, which would be her seventh at the U.S. Open and 23rd overall at majors, breaking Steffi Graf's Open-era record in that category.
Never one to shy away from non-tennis interests, Williams recently appeared in one of Beyonce's music videos and introduced a performance by her at the MTV Video Music Awards in Manhattan on Sunday night.
''Usually when people are there, I try to play better, especially if they're famous and they're doing so great at their job,'' Williams said. ''It's like I want to show them that I'm good at my job, too.''
Williams then tacked on two words at the end of that thought - ''minus today'' - just to be sure everyone understood how she felt about this particular outing.
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