Croatians Dino Mihanovic, left, and Josip Babic, center, joined their hosts including Christian Hotton, second from right, at the Argentine Embassy for the teams’ World Cup match. (Michael Robinson Chavez/The Washington Post)

Slobodan Silijeg sidled up next to Dino Mihanovic in the atrium of the Croatian Embassy in Northwest Washington, planted his nose into the taller man’s left shoulder and sniffed.

“This isn’t that new!” Mihanovic laughed, plucking at the red-and-white, No. 17 jersey he’d just pulled on over his shirt and tie.

Silijeg shot the counselor of the European Union to the United States a skeptical look, and they were both grinning as second secretary Josip Babic swooped into proclaim, “Okay, time to go!”

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Eight people sardined into the black stretch Chevy Suburban and the driver piloted it toward the Argentine Embassy, which had invited the Croats over to watch the match between their countries this past Thursday. The driver, from Cyprus, smirked slyly as he wondered aloud whether he should root for Argentina.

The 11-minute drive was filled with every possible scenario for Croatia to advance to the knockout stage; everyone agreed that a draw was probably the best hope against a giant such as Argentina. If Croatia did that and then beat Iceland in its final group game Tuesday, Mihanovic said, that should be enough.

“Worry about Iceland later,” said Lara Romano, the Croatian deputy chief of mission, as everyone piled out onto the sidewalk. “This is Argentina.”

Inside the four-story beige building, only two colors existed: blue and white. Clusters of balloons, streamers and Argentina jerseys were all illuminated by blue-and-white mood lighting. When the Croatians reached the main room, the one with the tables of cheese, crackers, grapes, empanadas and malbec wine, a man emerged from the crowd.

“What is this Croatian invasion?” said a beaming Gerardo Díaz Bartolomé, the deputy chief of mission.

“Lots of pressure on you guys,” Babic said. “Messi has to win.”

“No problems,” Díaz Bartolomé said, grinning and pointing to a spiral staircase. “We’ve got Mandžukić kidnapped upstairs.”

The Croatians’ belly laughs became nervous ones inside the room, which was set up like a movie theater with a big screen and 70 plush seats. There were five Croatians, six when the driver clapped for the Blazers, and they seemed fewer as howls surrounded them: “Vamos, vamos Argentina! . . . Vamos, vamos a ganar!”

On the screen, La Albiceleste attacked.

“We get lucky here,” Babic said after an open shot sailed into the Croatian goalie’s arms.

“We get lucky here,” Babic said again after a shot flew wide.

“How much longer can we get lucky?” Babic said after a shot flew high and the first half drew to a close, somehow scoreless.

Then, in the 53rd minute, the stalemate broke when the Argentine goalie made an inexplicable blunder, mishitting the ball so it floated in the air for Ante Rebic to slam home. In the back of the dark room, a man screamed in Spanish and kicked and punched a chair while a handful of blue-and-white fans filed out. Romano put a hand on top of her red “Hrvatska” hat in disbelief and chanted: “Replay! Replay!”

From then on, the Croatians hooted every time Argentina played a ball back to its goalie. They tried and failed to keep the laughs to themselves when Argentine legend Diego Maradona appeared distraught on the TV screen, chewing his thumbnail.

On the second goal, an 80th-minute rocket from Luka Modric, Babic thumped his chest as his friend hollered, and more Argentines filed out. By the 90th-minute dagger, two-thirds of the room was empty. The moment the referee’s final whistle tweeted, the Croatians beelined for the exit. They were stopped only by Díaz Bartolomé, who patted the shoulder of Mihanovic’s No. 17 jersey and said, “I’m happy for you.”

Once outside, the Croatians gathered in a circle.

“I can’t believe it,” Babic said, speaking for all of them.

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