"Are you kidding me?" he says.
Rookie guard Allonzo Trier had just been whistled for a crucial goaltending call with 0.4 seconds to play and the New York Knicks were on their way to a fifth consecutive defeat.
"Yeah [the ball] was coming down," Kanter says as replay confirms the call that all but sealed the game. He slaps his knee in disgust and slams his left hand on the base of the couch.
"Come on, man!" Kanter says, his No. 00 road Knicks jersey -- worn the entire game -- wrinkled a bit as he throws his hands up.
Kanter is some 3,500 miles from his teammates as he watches the Knicks' 101-100 loss to the Washington Wizards inside London's O2 Arena, insisting he is "trapped" in the United States due to his vocal criticism of Recep Tayyip Erdogan, president of his native Turkey.
"It's sad. I could be there with them. But it's just, sometimes there are bigger things."
Kanter appears relaxed as the Knicks build a 19-point lead in the first half, resting his left arm on a couch cushion behind him while grasping his phone with his right. Midway through the second quarter, he retweets an article detailing NBA commissioner Adam Silver's support of his decision to stay home from the London trip.
But as the Knicks' lead starts to shrink in the fourth quarter, Kanter's body language changes. He's sitting up, alert and wincing with every Wizards basket.
"That's a tough shot," Kanter says as Wizards guard Bradley Beal hits a 3-pointer with 7 minutes to play.
When Kanter sees fellow Knicks center Noah Vonleh get the ball in the post with 40 seconds left and New York down one, he can't help but put himself on the O2 Arena hardwood.
"Man!" Kanter said. "If I was there!
"I usually play good against Washington. So I'm like, man, I could be there and get a double-double."
About 48 hours before the Knicks' meltdown, Kanter was in Washington meeting with several lawmakers to discuss what he sees as the damage done to his home country. The international arrest warrant and extradition request for Kanter issued by Turkish prosecutors earlier this week came up in conversation.
"They said don't worry about it," Kanter says. "There's no way they can extradite me back in Turkey because you didn't do anything wrong here."
The 26-year-old said he was "angry" over the accusation that he was a member of a terror organization. "Terrorist is a heavy word," Kanter says.
"I have a platform. I'm using this platform and the Turkish government hates it. They're scared of my platform and that's why they called me a terrorist."
Kanter supports Fethullah Gulen, a U.S.-based Turkish cleric whom the government has accused of masterminding a failed military coup in 2016. Gulen has denied the allegation. Kanter's criticism of Erdogan and support for Gulen have made him a target for the Turkish government, he says, leading to prosecutors seeking criminal charges against Kanter and his father. It's also made Kanter a target of death threats on social media.
"I'm getting hundreds a day," he says. "I'm not saying they could [harm me] here, but there could be one crazy supporter that can do anything."
It's all enough to sometimes keep Kanter, who always appears jovial and care-free with teammates, from getting a good night's sleep.
"You have to put that happy mask on," Kanter says. "[But] thinking about all these conversations, thinking about my family, not just my family, people's families in Turkey, thinking about how can I do more to help them, it definitely keeps me up."
A few hours before tipoff Thursday, Kanter was working out at the Knicks' practice facility in a relatively empty gym. Kanter was playing one-on-one with his brother and running to stay in shape -- a far cry from a traditional Knicks practice.
"I was just doing my own stuff and I'm like, man, what am I doing?" Kanter says.
Things will get back to normal for Kanter this weekend. He won't have to check social media to keep up with his teammates. He'll be able to join when they make plans on the teamwide group chat for dinners, mall trips and haircuts.
"I just want to go do my job," Kanter says. "Because of all this, I couldn't do my job."
Whether Kanter will have this job with the Knicks for much longer is an open question with the trade deadline approaching. Several teams have talked to New York about potential deals involving Kanter, per sources. ESPN's Adrian Wojnarowski reported last week that the Sacramento Kings and Knicks talked about a trade involving Kanter and Zach Randolph as a swap of expiring contracts.
Kanter knows the talks probably will continue until the Feb. 7 trade deadline.
"People know I love the Knicks. And I want to be here, and I want to play basketball here and I want to win here," Kanter says. "But if they trade me, I cannot say, 'No, I don't want to get traded.' But I don't want to get traded.
"I guess with all the rumors, we just have to wait and see what happens."
Kanter also knows that New York hopes to attract a top free agent this summer. To have enough cap space to sign a max free agent, the Knicks would have to renounce their rights to the seven-year veteran. That's why Kanter paused Thursday when asked if he sees himself as part of the Knicks' future. "I would love to be part of the future of the Knicks, of course," he says.
For now, he'll settle for being back in the same country as the Knicks.
Beal and Porter lead Wizards to London win
Bradley Beal and Otto Porter Jr. combine for 46 points and 20 rebounds in a wild win over the Knicks in London.
Knicks fall to Wizards on goaltending call
Thomas Bryant's floater is blocked by Allonzo Trier but whistled as goaltending, and the Wizards take down the Knicks.