Born and raised in Orange, Calif., Johnson stayed home and attended USC, where he did something no one else has ever done. He helped the Trojans to four NCAA team titles (2009-12) and won two singles championships himself. In fact, he finished his career with 72 consecutive singles wins.
And then, he went pro. In 2013, his first full season, he won four matches at the ATP level -- and lost 10.
"I took the losses pretty hard," Johnson said Tuesday. "Every time I would lose it would be such a shock to the system. Mentally, the whole year got to me. My confidence level would go down.
"Everything needed to get better. This year, I have a new perspective. I'm looking at each match, thinking about what I did well and what the other guy did well. It's been a growing process for me, something more mental than physical."
The results can be seen in his career-high No. 68 ranking. Johnson, 24, has already won two Challenger titles, in Guadeloupe and Dallas, and had nice runs after qualifying in Auckland (quarters) and Delray Beach (semifinals). He is 6-6 in ATP matches and is already guaranteed a spot in the main draw at the French Open. He will play two events beforehand: the Bordeaux Challenger and the ATP event in Nice.
After an ambitious start to the season, Johnson is practicing, working hard in the gym, and getting some physical therapy for the ubiquitous tendinitis in the right wrist and shoulder. ESPN.com caught up with him after a practice session at USC.
ESPN.com: Your dad is a tennis coach and your mom's a math professor. That sounds like the perfect pair for a future pro tennis player.
Steve Johnson: Yeah it was a pretty cool deal growing up because I had the best of both worlds. My dad was taking care of the tennis and my mom had the schoolwork piece. Math is all about angles, so maybe some of that rubbed off.
ESPN.com: How has Craig Boynton, John Isner's former coach, helped you?
Steve Johnson: In all facets of my game. I've gotten a lot more consistent from the baseline. Regardless of the situation, whether it's match point down or looking at a break point, you just have to execute your skill set. When the time comes, you'll know you can make these shots. We've been practicing, trying to emulate what happens in the matches.
ESPN.com: You've already won two more matches than last year. What's changed?
Steve Johnson: Playing at the ATP level, I feel now like I belong and I'm a lot more comfortable in all these tournaments. This year I've done a great job of qualifying, too. On big points in big matches, I feel like they're not too big for me anymore.
ESPN.com: What areas are you most focused on improving?
Steve Johnson: I'm still focused on being in the best physical shape I can be in. Overall, I just want to continue to get better. This is a game where you're always trying to improve -- for me, particularly the backhand wing. I feel pretty confident with the slice, but hitting that passing shot or taking it down line for a winner, well, that felt uncomfortable for me. We spend a lot of lot time working on that.
ESPN.com: You're ranked higher than you've ever been, at No. 68, what are your goals going forward?
Steve Johnson: I don't want to put a number on where I want to be at the end of the year. I don't want to put that pressure on myself. I just want to keep my feet going forward, improving every day. When I sit back at the end of the year and I have no complaints, I'll know it's been a good year.