MASON, Ohio (AP) — The final step up to No. 1 was simply too big for Angelique Kerber — this time, anyway.

The world's second-ranked player wasted a chance to end Serena Williams' long run at the top. She fell behind at the outset, repeatedly missed routine shots and fell to Karolina Pliskova 6-3, 6-1 in the championship match Sunday at the Western & Southern Open.

On the men's side, Andy Murray also ran out of steam in the title match. He fell to Marin Cilic 6-4, 7-5, ending his career-best winning streak at 22 matches.

More was at stake on the women's side. Williams will be ranked No. 1 for the 184th consecutive week, two shy of Steffi Graf's WTA record that ended in 1997. And Kerber will remain right behind after her frustrating performance on Sunday, hoping for another chance.

"Everybody's talking about that," Kerber said. "If someday it happens, it happens, but I will not be making too much pressure on this. I've had such a great year so far and it's not over yet."

Williams, the two-time defending champion in Cincinnati, missed the tournament because of a sore shoulder, giving Kerber the opening to move ahead of her by winning the title. She was tired at the end of three hectic weeks that included an Olympic silver medal in Rio de Janeiro.

It was the biggest win of Pliskova's career, the 24-year-old Czech's first title in a premier tournament. She broke Kerber to open the match and won 17 of the first 24 points with shots that were right on the line in windy conditions. Pliskova had only six unforced errors during the 62-minute match.

Asked how she was going to get the winner's trophy home, Pliskova said she hadn't even thought about it.

"I was expecting I'm going to play good, but I wasn't expecting it that easy," Pliskova said. "I think she might be a little bit tired, or she felt a little bit of pressure on herself."

Kerber hardly moved when Pliskova ended it with a 115 mph ace down the middle. Pliskova took a few steps toward the net, stopped, clenched both fists and closed her eyes for a moment, letting it soak in.

Kerber badly wanted to win the Cincinnati tournament for the first time and join Graf as the only German women to be ranked No. 1 in the world. At age 28, she would be the oldest woman to reach the top of the WTA rankings for the first time.

The first seven days of the tournament included long rain delays. Cilic finished his three-set win in the semifinals at 1:35 a.m. local time, and was back on the court 14 hours later to play for the title.

Not that Murray had an easy time of it. He won his second Olympic gold medal in a four-hour match against Juan Martin del Potro in Rio de Janeiro last Sunday, flew directly to Cincinnati, caught a nasty head cold, and struggled to get through the week as his worn-out body repeatedly tightened up.

By the time he reached the semifinals, Murray appeared to have caught a second wind. He couldn't keep it up on Sunday, playing his 14th match in the last 15 days.

"I'm very proud of this week," Murray said. "Obviously today didn't go how I would have wanted. I certainly didn't expect to get to the final when I got here. It was a very, very positive week. I'm looking forward to a few days' rest."

The top of the men's bracket was depleted by injuries. Novak Djokovic and defending champion Roger Federer skipped the tournament because of injuries, and Rafael Nadal was beaten early as he works back from a two-month wrist injury. Murray was the last of the Big Four.

Cilic's win ended a streak of 18 straight Masters titles by one of the Big Four. The 2014 U.S. Open champion had never reached a Masters final, going 0-8 in the quarterfinals until this week. When he won on Sunday, he pumped both arms on the baseline, shook Murray's hand, then jumped and punched the air with a fist.

"It's definitely a big relief," Cilic said. "This is for sure a huge step forward."

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