Klahn, who won the NCAA singles title in 2010 as a sophomore, has taken a wild ride the past six weeks and it's just the beginning.
Klahn has been a professional tennis player for all of 14 months and, like a grad student, has continued his education at a higher level.
Recovering from a first set loss and saving one match point in the second set, Klahn clearly has his sights set on an advanced degree in tennis.
Klahn defeated Great Britain's Daniel Evans, 3-6, 7-6 (5), 6-4, in a wildly entertaining championship match of the $100,000 Comerica Bank Challenger at the Seascape Sports Club in Aptos.
"I was happy that match point and get the tiebreaker," Klahn said. "I was trying to stay in the moment and stay composed. I had to trust my serve and forehand. I think there was a high level of tennis played by both of us."
He's taking the next two weeks to prepare for the U.S. Open, at which he received a wild card because of his play on the USTA Challenger circuit.
After playing five tournaments in six weeks, reaching the final in three of them, he needs the time to relax a little bit and refine some of his skills.
"It's right around the corner," Klahn said. "I really do need to work on a few things."
His coach, Lee Merry, has him grounded. He took plenty of time discussing things with Klahn after Sunday's title.
"I'm playing with a lot more confidence and I have a clearer idea of what I'm trying to do on the court," Klahn said after receiving his winning share of $14,400. "Last year I was two months out of college and new to the pro tour. It's made me aware of my improvement."
He seems to enjoy doing it the hard way too. He played 3-set matches over the final three days of the tournament. In addition, he's spent most of the summer in 3-set matches.
"I've had plenty of court time," he said. "My fitness is a testimony to my work with the USTA, on court with my coaches and my strength work in the weight room."
Stanford coach John Whitlinger and volunteer assistant J.J. Whitlinger were on hand to watch the title match. Klahn certainly impressed them with his play.
"You can see he never gives up," John Whitlinger said. "It's his consistency. You look at his summer and he's played in three finals. He's played a lot of matches. When you start winning, it becomes a habit. Whether you're playing a major or a challenger, it's the same thing. It's good to play a lot of tennis."
Klahn, who won an ITF Futures tournament in March, has been elevating his game since turning pro. It showed when it came to the big points.
Klahn needed to save one match point, which he did with an ace, in the second set. He was down, 4-3, in the tie-breaker before winning three consecutive points.
The third set was hard-fought, with both players aggressively attacking the net at times. Klahn recorded his first break point on match point.
Evans won 51 percent of the points but eight double faults hurt him. Klahn had one double fault to eight aces, including twice on a second serve.
Klahn utilized his forehand to score big points. It's a forehead that Whitlinger calls "world class."
For Klahn, it's his biggest weapon.
"I tried to use it as much as possible and to be aggressive with it," Klahn said. "I was able to hit every spot on the court."
Klahn clinched his wild card to the U.S. Open by beating Wayne Odesnik, the tournament's No. 5 seed, in the quarterfinal round.
"I was a little nervous in the third set against Wayne," Klahn said. "I knew what was on the line and I tried not to think about it, but I did. It was about how well I handled it."
Klahn takes 32-12 overall singles record to New York, where he will be making his fourth consecutive appearance. He reached the Round of 64 last year, losing to then 14th-ranked Richard Gasquet of France.
In the meantime he's making plans to visit Stanford a few times this fall to watch a few football games along with visiting former tennis teammates and coaches.
"I had a great four years there," Klahn said. "It was a lot of fun, a lot of great memories. It's always nice to come back here. I'm very invested in that. I feel like this is my second home and to win my first Challenger here was awesome."
He's part of a youth movement among American tennis players and practices with several of them. He sees a future for the group.
"I feel like there is a good group of Americans coming up and playing well," Klahn said. "A lot of young guys."
One of his long-standing rivalries is with USC grad Steve Johnson, who won last year's Challenger (Klahn lost in the quarterfinal) and was eliminated in the second round this year.
Johnson won NCAA singles titles in 2011 and 2012. Klahn and Johnson have known each other since they were teens.
"It's funny, I've never played him as a pro," Klahn said. "It seemed like I was playing him every other week in college. We're still good friends and we trained together last year."
Klahn isn't looking any farther than the U.S. Open these days. There's a future, for sure, and he knows not to dwell on such things. There's plenty of time to prepare for the end of his first full year as a professional.
"I call tennis my full-time job now, though I don't consider it a job," Klahn said. "I enjoy what I do. It's very demanding and it's fun."
It's been over 10 years since he traveled out of state for the first time to play in a tournament ("It was in Arizona, not too far," he said). These days he's got the whole world to explore.