Millman indeed took the fight to the reigning Wimbledon champion in a showdown featuring the last two players to topple Federer this season.
He will play either Serbia's Novak Djokovic or Australian John Millman in the last four.
Nishikori is into his third major semifinal - all in NY - but is still in search of his initial Slam trophy.
Osaka was an easy victor in her quarterfinal, eliminating unseeded Lesia Tsurenko of Ukraine 6-1, 6-1 in all of 57 minutes.
Keys, a 23-year-old American who is seeded No. 14, overwhelmed Suarez Navarro with her powerful serve and groundstrokes, building a 22-10 edge in winners.
Naomi Osaka, of Japan, returns a shot to Lesia Tsurenko, of Ukraine, during the quarterfinals of the U.S. Open tennis tournament, Wednesday, Sept. 5, 2018, in NY.
"I've gotten a lot better managing my emotions once it gets to this part and knowing that everything is going to be probably more amped up", she said.
Top Trump economist says bombshell NYT op-ed 'might be a fraud'
However, it also used the term "first principles", a phrase often used by General Jim Mattis, Trump's national security adviser. Current and former members of President Donald Trump's Cabinet are pictured in this Oval Office photo taken on March 13, 2017.
"I wish I don't go to five sets every time, " Nishikori said.
It wasn't the cleanest of matches as the grueling heat at Arthur Ashe Stadium seemed to force both competitors into a slew of mistakes over the course of the four-plus hour match.
When is Marin Cilic vs Kei Nishikori on and what time does it start?
Despite having never won a Grand Slam, just 11 career tournaments, Nishikori is in the same league as Grand Slam kings Roger Federer and Rafa Nadal when it comes to pitching products.
She raced to a 3-0 lead in the first set and then 4-0 in the second against the shaky Tsurenko, who finished with more unforced errors than points in her first major quarterfinal.
John McEnroe was accused by American pro tennis player Mitchell Krueger of "ripping" Millman in the preview as the story continued that Federer lost the match because of the stifling NY heat and humidity rather than his opponent.
Kei Nishikori outlasted Marin Cilic in a rematch of the 2014 U.S. Open final, moving into the semifinals with a 2-6, 6-4, 7-6 (5), 4-6, 6-4 victory.
But after reaching the final in Monte Carlo, the French Open fourth round and the Wimbledon quarter-finals, Nishikori believes an elusive first grand slam is within reach.
"From that point on, I felt the match was quite even", he went on.
In the third set, Djokovic again claimed the break.
This night was cooler, as the temperature dipped into the 70s, but the humidity was above 80 percent, so with Millman drenched, he sought permission for a wardrobe change at 2-all in the second set.
"I was struggling, he was struggling", Djokovic added. Just put me back a bit on my back foot.
He said: "He's got one of the best two-handed backhands in the game and very quick. So it came down to a couple points".
Djokovic was not to be denied though, as he timed the final break of serve to perfection, grabbing the advantage in game nine before serving out to love to seal his passage into the final four.
Nishikori's relatively week serve could be the deciding factor here, as if Cilic can get into his groove he will look to punish that aspect of his opponent's game, especially the second serve.
US Open: Osaka makes history
Meanwhile, Osaka won a Masters title at Indian Wells and with her strong run in NY , where she will next play 2017 U.S. So far in this Open, she's held opponents scoreless in three sets, and she's dropped only one set thus far.
We knew immediately something was wrong. "She walked in the door and he shot her", Cain told the Cincinnati Enquirer . He says an investigator told him the suspect had enough ammunition to cause "a bloodbath beyond imagination".
While speaking at the University of Illinois, Obama criticized what American politics have become, specifically targeting U.S. On Thursday, the former president is scheduled to campaign in Cleveland for Richard Cordray's campaign for Ohio Governor.
In another consequential exchange, Kavanaugh would not say if a president was legally obligated to comply with a subpoena. But Kavanaugh's nomination languished for three years, as Democrats fumed over his participation in Bush's recount team.
The problem is that there are a great many reproductions out there and people believed that these were the stolen slippers. Tips led divers to a lake near Grand Rapids in June of 2015, to scour the bottom in search of the ruby slippers.
An official of the Kolkata Traffic Police said, "We expect traffic jam because the Majherhat bridge has collapsed ". It runs over the Majerhat Railway Station and connects the city centre to Behala and other southern suburbs.
Gabe, Jelly, me, Khalil, we all saw it coming". " We have a lot of holes, and we have to do what we can to fill them ", he adds. Said Nagy: "I'm not going to sit here and say 100 percent because we haven't declared that yet". "We all knew.
Morton claimed he couldn't keep up with the company's jarring path. "Tesla 1st, 2nd & 3rd in August sales", Musk tweeted . Musk explained that he's "not a regular smoker of weed" because he "doesn't find it's very good for productivity".
While THR didn't include a cause of death, The Daily Mail reports that Reynolds died of a heart attack. Reynolds was married to actresses Judy Carne from 1963 to 1965 and Loni Anderson from 1988 to 1993.
The high rig count has helped lift U.S. crude oil production by more than 30% since mid-2016, to 11-million barrels a day. While the USA crude imports surged by one million barrels a day, exports fell by more than 250,000 barrel per day.
Nadal sails into US Open semis
Dominic Thiem , of Austria, reacts after losing a point to Rafael Nadal , of Spain, during the quarterfinals of the U.S. At the end of four hours and 49 minutes, at 2:04 am NY time, that's the word Thiem was left ruing.
Musk muses about life over weed and whiskey
Musk stunned investors a month back with tweets saying he had funding to take the company private for $420 per share. Musk has said he expects the company could turn profitable in the second half of this year.
What happened to Australian model Sinead McNamara?
Local media reports Baillères had left the boat on Tuesday and Sinead was left onboard with the rest of the boat crew. The superyacht on which Australian model Sinead McNamara died has reportedly left the Greek port where it was moored.
Kremlin dismisses Trump warning on Syria's Idlib
Syrian President Bashar al-Assad meets with Iran's Foreign Minister Mohammad Javad Zarif in Damascus , Syria , Sept. 3, 2018. The Kremlin said the fightes in Idlib were blocking peace efforts and threatened Russia's military presence in Syria.
Gulf Coast prepares for Gordon's expected arrival as hurricane
The Naples Daily News reports that Naples beachfront stores were getting hardly any foot traffic Monday as the storm approached. A storm surge warning has been issued for the area stretching from Shell Beach, Louisiana, to Dauphin Island, Alabama.