When 20-year-old Ethan Quinn walks on court Thursday evening for his second-round match at the Dallas Open, he will face more than the No. 9 player in the PIF ATP Rankings. Quinn will take on a friend and mentor in Tommy Paul.

“I need to make sure that I go in knowing that I obviously admire Tommy,” Quinn told ATPTour.com. “But I've got to make sure that I don't take that admiration and let it get in the way of my own success.”

Quinn first met Paul when he was 16. The California native was in Florida for the Orange Bowl, an international junior tournament. The pair practised at Evert Tennis Academy the day before Quinn competed in the event.

“Now that I live in Boca, I see him a lot more often,” said Quinn, who sat in Paul’s box for his win against Jenson Brooksby on Tuesday evening. “But before I moved down there, I'd stay in touch with him a little bit here and there, certainly text him on Instagram or whatever like that.”

Quinn’s longtime coach, Brad Stine, just began his sixth season as Paul’s coach. The four-time ATP Tour titlist has become a good friend and, in many ways, an example for the former University of Georgia student-athlete. Fittingly, Paul planned to play college tennis for the same school before turning professional.

“He's a funny guy. So easygoing. He goes out and has fun with whatever he's doing, whether it's fishing on the boat, going on the beach, practising working out with [strength-and-conditioning coach] Franco [Herrero],” Quinn said. “There's always a smile on his face, and it's pretty fun to see the way he works out, the way he's able to enjoy what he's doing. It lets me know, this is a fun thing to do, this is a fun job. It's not something where I'm hating it. So it's making sure I put a smile on my face just knowing that I'm having fun out there and doing the right thing.”

Quinn, whose full-time traveling coach is Brian Garber, was a highly touted prospect when he won the 2023 NCAA Singles Championships and turned professional shortly thereafter. But it was not an easy transition to the ATP Tour. He quickly lost seven consecutive matches and the “mental monkey” became difficult to deal with.

“I never expected myself to go pro and that to happen. There was a lot of self doubt, and a lot of, ‘Man, should I go back to college? Maybe I wasn't ready for this’,” Quinn said. “And even last year, before the US Open, there was a little bit of that same feeling. Had talked about it a little bit with my coaches, ‘Maybe you should go back to college. Maybe not. How do you feel about it?’ And at the time I was like, ‘Man, maybe that would be fun to do that’. But in the long run, I don't think I'd be where I'm at now.”

After qualifying in Dallas, an ATP 500 event, and winning his first-round match in the main draw Monday, Quinn is up to No. 149 in the PIF ATP Live Rankings. The American overcame the “mental monkey” last year, with a big breakthrough in November in Champaign, where he won his first ATP Challenger Tour title without losing a set.

In some ways, Quinn’s delayed rise has not been dissimilar to Paul’s. The 27-year-old was one of the world’s best juniors when he turned pro, but it took until age 22 to crack the Top 100.

“Tommy has talked about it a little bit when he was struggling when Frances [Tiafoe], Taylor [Fritz]and Reilly [Opelka], were all exploding. He was a little bit further back and it was hard for him,” Quinn said. “[It was the] same thing for me, when I was seeing a lot of the other young American guys, or even guys like Joao [Fonseca] and Martin Landaluce and other young guys that aren't from the U.S. When I saw them doing well, I was like, ‘Man, I need to catch those guys’. But he reassured me: ‘You don't have to worry about it, it's your own path, it's your own race. Don't try and rush it. When the time's right, it'll come’.”

The morning after Quinn’s opening main-draw victory, Paul enthusiastically congratulated his friend on his win against Trevor Svajda. It was a straightforward 6-4, 6-2 victory for Quinn, whose forehand was the biggest weapon on the court.

“When I first went pro, I think it was really hard trying to figure out what my identity was on court. When I was in college, I just had this easy power where I was able to win matches by hitting guys off the court. I wasn't really able to play with too much structure, because I knew that I was maybe better than the guy, or if I really needed to I was just going to overpower them,” Quinn said. “On Tour, you don't really have that option. You can't really just overpower guys because everyone's so good, everyone's such a good ball striker. So I really had to create this new identity and new structure to my game.”

Quinn has also adjusted his efforts off the court. “Sometimes I’m a little bit uptight”, he said, adding that Paul taught him to be a bit more easygoing and enjoy everything and understand that not everyone who dreams of becoming a professional tennis player gets to live this life.

“I think the biggest lesson I've learned is that when you're 20 years old, it's not often you're getting to travel the world,” Quinn said. “It's a pretty amazing job that at 20 years old, I get to travel the world for my job, get to explore new places, get to do something that I love, something that I dreamed of when I was a kid. So I think it's just enjoying the entire process and not making it too stressful.”