MASON, Ohio (AP) Angelique Kerber reached the Western & Southern Open final Saturday, leaving her one win away from unseating Serena Williams at No. 1.
Kerber took control after a 33-minute rain delay in the first set and beat Simona Halep 6-3, 6-4 in humid, windy conditions, putting her within reach of the world's top ranking. Williams has led the WTA rankings for 183 consecutive weeks, the second-longest such stretch.
A win on Sunday over 15th-seeded Karolina Pliskova would move Kerber to the top spot in next week's rankings. Williams dropped out at the start of the tournament because of an inflamed shoulder, leaving her ranking vulnerable.
Andy Murray extended his successful summer - another Wimbledon title, another Olympic gold medal - by reaching the final as well, giving him a chance for a third Cincinnati championship.
More is at stake in the women's title match. Kerber has tried to avoid thinking about No. 1 because she didn't want to put any more pressure on herself. Now, there's no avoiding it.
''I've had a lot of ups and downs the last few years and a lot of experiences from which I've learned,'' Kerber said. ''I think I'm one of the best tennis players.
''One match away, still a long way to go.''
She'd become only the second German woman to hold the top spot. Steffi Graf's reign at No. 1 ended in 1997. It would be Kerber's first title in Cincinnati - she lost her other finals appearance in 2012.
Halep was on a hot streak, winning back-to-back titles at Bucharest and Montreal. She'd also beaten Kerber in their four matches on hard courts this season, although Kerber won at Wimbledon.
Kerber led 4-3 in the first set when rain forced the delay. She won eight of the next nine points to take the first set, then pulled ahead 4-0 in the second set, pumping her right arm in celebration as the games piled up.
Pliskova advanced to the championship match for the first time by beating Garbine Muguruza 6-1, 6-3 in an earlier match. She was well aware of the stakes on Sunday.
''I know it,'' she said. ''For me, doesn't really mean anything. For her, yes. I don't know if she would be a little bit stressed or something, but I would love to have her as a No. 1 after a few years. But I'll do anything for her not to get there, if she wins (in the semifinals).''
In the men's bracket, Murray beat Milo Raonic 6-3, 6-3, also overcoming a brief rain delay in the first set. He's won his last 22 matches, a career best. And he appeared fresher on Saturday after pulling through a draining summer of success.
After beating Raonic for his second Wimbledon title and getting another Olympic gold medal in Rio de Janeiro, he came to Cincinnati worn out. He developed a bad head cold and had a stiff back that limited his movement during the quarterfinals. He was much sharper on Saturday with only 11 unforced errors.
''I'm not going to be fresh,'' Murray said. ''I've played a lot of tennis the last few weeks. This week has been hard for me, coming from Rio. Tomorrow is going to be my first match during the day. Every player will tell you the conditions are different in the daytime.''
The men's bracket was wiped out by injuries. Novak Djokovic and Roger Federer skipped the tournament, and Rafael Nadal was knocked out early as he plays back into shape following a severe wrist injury.
By reaching the finals, Murray made it 33 straight Masters championships involving at least one member of the Big Four - Murray, Federer, Djokovic and Nadal. One of them has won each of the last 18 Masters championships.
Murray will face Marin Cilic, who rallied to beat unseeded Grigor Dimitrov 4-6, 6-3, 7-5 in a rain-delayed semifinal that ended at 1:36 a.m. local time.
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