Part-time player Matija Pecotic has had to request more time off work after claiming a shock win in the Delray Beach Open.

Pecotic is ranked 784th in the world and had to come through qualifying to reach the main draw, but on Tuesday beat former top-10 player Jack Sock 4-6 6-2 6-2.

The 33-year-old Croatian holds a full-time job in a real estate investment firm and had to leave work early for his match with Sock, with his boss watching from the players’ box on court.

“I certainly didn’t expect to win, but certainly didn’t come into the match thinking that I’m definitely going to lose,” Pecotic said, quoted on the ATP website, after his first ever main-draw win.

“You’ve got to be realistic. This is a former top-10 guy with an incredible amount of tennis experience, with a huge serve.

“He came out serving 134(mph) on the first serve. It would be arrogant to think that I’m going to come out and expect to win.

“But I certainly figured if I could sink my teeth into the match and work on the two or three patterns that I prepared before, that I’m going to have a chance.

“And then let’s see… if I was going to fall under pressure or not be able to serve it out at some point. But I didn’t and I got the win.

“I had to leave work early. I had to send an email to the whole team. (My boss) let me off. I’m going to have to ask for another day off (on Wednesday).”

Speaking after qualifying, Pecotic said that he typically works from 9am until 6pm and tries to play tennis before work.

“I absolutely love this game and I know it’s not forever and I’m 33,” he said.

“I try to maximise each day. I try to train every morning if I can, five, six times a week. Sometimes I train with my boss, who is 70 years old. This week I trained with a guy who is probably in his late 50s. But you find creative ways to work around it.”

Pecotic will face Marcos Giron in the last 16 on Wednesday.