By Bill Scott, dpa

New York (dpa) – Angelique Kerber became the 22nd woman to earn the WTA top ranking, with the German celebrating her success with a 6-4,
6-3 semi-final defeat of Caroline Wozniacki on Thursday at the US Open.

The 28-year-old will become the top WTA player on Monday after Karolina Pliskova knocked a limping Serena Williams out 6-2, 7-6 (7-5); that win pushed Kerber to the summit.

Kerber will have something to prove after going down to Pliskova in the August Cincinnati final. Steffi Graf was the last German to win the New York trophy, lifting it in 1996.

Kerber was never in doubt against former number one Wozniacki, making a late-season comeback after a spring ankle injury and two months out of the game.

Kerber ran off a 4-0 lead in the opening set before claiming it. She moved up a double break in the second but recovered after being broken while for the match before breaking back to finish the effort.

She will be playing her third grand slam final of the season; Kerber beat Williams for the Australian Open title and lost to the American at Wimbledon.

«It is just incredible, it’s a great day,» the winner said. «I was focussing on this match only, Caroline is a tough player.

«To be in the final as number one is great, it all sounds amazing. To be the next one (German number one) after Steffi is amazing – I think she is proud of me.

«Against Pliskova, I’ll try to take my revenge. I’ll give my best and will be trying to win the match, of course.»

The upset of Williams, the top seed, meant the American was denied the chance to continue her reign atop the WTA list after three and a half years.

A year ago, the 34-year-old was beaten at the same stage by Roberta Vinci.

A subdued Williams was 24 hours rewmoved from a three-set quarter-final defeat of Simona Halep. But she repeatedly insisted that back-to-back matches were not a factor in her loss.

«I wasn’t tired from yesterday’s match. I’m a professional player; been playing for over 20 years.

«If I can’t turn around after 24 hours and play again then I shouldn’t be on tour. So I definitely wasn’t tired from yesterday at all. It wasn’t a five-hour match. I practised three hours, so it wasn’t that huge of a deal.»

Williams said a knee problem first popped up in the early New York rounds but refused to go into any detail. She also did not speak to any detail regarding the loss of the top ranking which she had held since 2013.

«I have been having some serious left knee problems. I wasn’t tired.
Fatigue had absolutely nothing to do with it. If I was tired I should definitely get into a new career.

«I wasn’t able to move the way I wanted to move. When you’re injured you’re thinking of other things when you should be just playing and thinking of your shots. My mind was just a little bit everywhere. But it was what it was.»

Williams ended disappointingly with an error followed a double-fault on match point.

Pliskova was in mild shock from her success. «I don’t believe it – actually I do,» said the Czech. «I come to every match believing I can beat any player.

«This is amazing. Serena fights hard, she’s a champion. My serve was the difference today. She was going full power to me. Serve was the key to how I won.»