Kei Nishikori, Serena Williams win thrillers in U.S. Open quarterfinals

They gave the people what they wanted and needed on an often mesmerizing day and night of tennis at the U.S. Open on Wednesday.

Two enthralling matches pushed two proud champions — Andy Murray and Serena Williams — to the brink, requiring a decisive set in both contests and testing their bodies and minds.

Williams emerged to play another day, Murray fell just short.

They pretty much salvaged what had been a recent run of drab matches at the Open. The top-seeded Williams faced her first serious test in the form of No. 5 Simona Halep of Romania and prevailed in their quarterfinal match, 6-2, 4-6, 6-3. Williams is two victories away from her 23^rd Grand Slam singles title and seventh U.S. Open championship.

That came after Murray fell to Japan’s Kei Nishikori in a five-setter that lasted nearly four hours.

Halep didn’t make it easy on Williams, who lost a set for the first time in five matches and dropped her serve for the first time in the tournament, twice in fact. She went four of 20 on break-point opportunities and hit 18 aces.

“I think there’s a huge enjoyment in three-set matches, but I feel like you don’t get that appreciation until later,” Williams said. “Obviously in the moment you want to win fast and you want to win easy and win in straights.”

Halep saved 12 break points in a hard-fought second set, including seven in one game. ““I wasn’t very happy about that. I tried not to let that get me down,” Williams said.

Williams will face No. 10 Karolina Pliskova of the Czech Republic in the semifinals Thursday night. Pliskova defeated Ana Konjuh of Croatia, 6-2, 6-2, in an earlier quarterfinal.

One reporter brought up the fact that Pliskova has a twin sister and asked Williams how tough it would be for Williams to have “an identical copy” floating around.

“It would be a living hell,” Williams said, drawing laughter.

Halep-Williams featured superb shot-making. Inexplicably, the quarterfinal between Nishikori and Murray turned early in the fourth set on a loud noise that sounded a lot like a gong. It went off when Murray had a break point in the third game and the chair umpire ordered the point replayed.

An unnerved Murray went into a free fall — dropping that game and, in all, losing seven straight games. He recovered sufficiently to make the fifth set a compelling contest. But Nishikori survived his own shaky moments to hang on, winning, 1-6, 6-4, 4-6, 6-1, 7-5, in 3 hours 58 minutes.

It has often been said the Open can resemble a Gong Show with the crazy night matches, the sound and noise all over the grounds. Essentially the opposite of Wimbledon.

The U.S. Tennis Assn. said in a statement, regarding the noise, one of the three digital audio sound processors in Arthur Ashe Stadium had malfunctioned.

“It’s a little bit different that the other Grand Slams,” Nishikori said. “I think it’s more loud and it’s more like, you know, big party on the court.”

Not only did the gong noise get to Murray, a rain delay caused the roof to be closed in the second set. He was also bothered by what looked like a moth or a butterfly on the court.

“Under the roof, he was able to dictate more of the points,” Murray said. “He was playing closer to the baseline than me and taking on the ball a little bit more.”

This was a rematch of their semifinal meeting at the Olympics last month in Brazil. Murray won that, and, in fact had lost to Nishikori only once in eight matches before Wednesday. He was on a 26-1 run, which included Wimbledon and the gold medal in Rio.

“I have won some over the last few months I should have lost,” Murray said.

Nishikori, an Open finalist in 2014, will face either No. 3 Stan Wawrinka of Switzerland or wild-card Juan Martin del Potro of Argentina in the semifinals. They were playing after midnight in New York.

The rain delay helped Nishikori adjust his tactics, following a brief consultation with coach Michael Chang, the former French Open champion. He needed to regroup after having led, 4-3, 40-0 in the fifth set and lost the game, notably netting a forehand volley at 40-30.

“You can’t dwell on that,” Chang said. “For us, as coaches and people who are trying to encourage him, we can’t dwell on that either. It does us and him no good if he spends the next game thinking about it, the match is gone. We were telling him, ‘Forget about it. It’s gone.’ “

Nishikori broke Murray at 30 with a lunging volley to take a 6-5 lead in the fifth and kept it together and held serve to seal the victory.

“There were many up and downs. I tried to stay calm,” Nishikori said. “I think that’s the most important thing I did today.”