(NEW YORK/CBSNewYork) – You would think Alec Joseph’s single “Where Did Summer Go?” was a pop tune about the warm and lazy season that always seems to go by too fast, but it’s not.

“I actually wrote it about a girl named Summer,” the singer-songwriter told CBS Local. “That relationship we had a few years ago went by so quickly, and then she stopped speaking to me, it was like – What happened? Where did Summer go?

Fresh from his tour with the a cappella supergroup Pentatonix, Joseph’s path to fame started not in the recording studio but on the court behind a net.

“I actually started off as a tennis player,” he said. “You don’t really hear that often in connection with tennis, but I made my transition when I was about 14-years-old.

“I was always doing school shows and plays and at camp and stuff like that, but I was a competitive tennis player and I loved what I was doing,” Joseph said. “People would come up to me after the shows for music and say, ‘You really inspired me to do music, I want to music because of you.’ I thought, that inspires me to do music – I can really make a difference in the world through music.”

So what’s it like to break into the pop business?

“The reaction has been so awesome, it’s only been out for a few weeks and it already has a 100,000 streams, so insane,” he said. “I best thing for me, the best feeling is hearing people sing back the words to my songs. That means the world to me. I write these songs in my room, or with a few people in rooms, to see people connecting with the songs means the absolute world to me.”