LONDON—You never know who you'll meet on a London street at 4 a.m.

A sleepy Jack Sock and his girlfriend, Michala Burns, ran into Rafael Nadal, Dominic Thiem and their respective teams out on the street after a 4 a.m. fire alarm forced them to evacuate their second-floor hotel rooms early this morning.

Watch: Sock Squeezes Past Cilic in Thriller

The alarm was jarring and the timing made Sock realize it wasn't a test.

"It was probably one of the most annoying noises I've ever heard in my entire life," Sock told the media after his 5-7, 6-2, 7-6 (4) comeback win over Marin Cilic today. "We're on the second floor of the hotel. I guess whatever happened in the hotel was on the second floor.

"I guess from what the workers at the hotel said, the location of your room is how loud the alarm is. We are right there, kind of right in the center of it. It literally sounded like the intercom I thought was in our room. Super loud, super annoying. It went on for a while."

Fortunately, there was no fire and no one was injured, Sock said, though the experience gave new meaning to the concept of "chilling with Rafa."

"At first I didn't know if it was a test or whatever," Sock said. "Then I realized it was 4 a.m., so I hoped it wasn't just a test from the hotel.

"I went outside, saw Rafa, saw Dominic. Everyone was all bundled up, freezing cold, just wanting to get back inside. Yeah, it was pretty miserable, to be honest."

Asked if Rafa and crew were clothed or at least wearing pajamas, Sock replied "Yeah, everyone obviously put on clothes. It was pretty cold outside. Some more (clothed) than others."

Nadal, who pulled the plug on his 2017 season following last night's loss to David Goffin, got quite a wake-up call on the first night of off-season vacation.

For Sock, the blaring alarm was more annoying than the biting winter cold.

"I stayed in the room for a while, which obviously probably isn't the smartest thing to do, if there had been a real scare," Sock said. "Not even sure what the exact reason why the alarm went off. But it was unbearable to stay in the room, it was that loud and annoying. That's more the reason why we left.

"My girlfriend and I left and went outside. We saw everyone outside. The process, I probably waited in the room for five, seven minutes, then probably outside for another five or seven. The whole thing was probably 15 minutes of freezing, miserableness."

Photo credit: Miami Open Facebook