Dominic Thiem acknowledges the crowd after a fourth-round loss at Wimbledon. (Clive Brunskill/Getty Images)

For years, Dominic Thiem has been considered tennis’s Next Big Thing. But over those same years, tennis’s current Big Things haven’t gone anywhere.

Thiem, a 23-year-old Austrian ranked seventh in the world, makes his Citi Open debut this week as the top seed in a 500-level tournament for the first time in his career. He arrives in Washington coming off his best Wimbledon ever, in which he reached the fourth round, and a clay-court season that included upsets of top-ranked Andy Murray in the Barcelona Open, No. 2 Rafael Nadal in the Italian Open and No. 5 Novak Djokovic in the French Open (where he reached the semifinals).

Thiem, who broke into the top 10 last year, might be a household name already, were it not for that pesky 35-year-old Roger Federer and the other trio of titans who agelessly continue to rule the sport. He has come to Washington hoping to take the next step in his precipitous climb.

“Of course it would be really nice,” Thiem said of winning the Citi Open, “but the main priority is to find the good game, and it’s the start here of a very long trip. And I’m doing it for the first time, to come here to Washington, because I want to play a good hard-court swing. Previous years I was always coming from Europe, from clay, and it didn’t work out that well. I hope it works out well from the first week on.”

Born of a tennis family — both his parents are coaches — Thiem counts among his more distinguishing attributes a preternatural calm, grace on the court and a one-handed backhand taught by his lifelong coach, Gunter Bresnik. The latter has served him particularly well on clay, on which he has won six of his eight career titles.

His maturity, too, made him a favorite member of the next generation. Unlike many players who cycle through coaches seemingly on little more than a whim, Thiem has stuck with Bresnik since he was young. On Monday, he spoke to the stability that brings to his life.

“Of course it’s an unusual thing here in tennis and in every modern sport,” Thiem said with a small smile. “But I hope, basically, that it stays like this for all my tennis life.”

The hype hasn’t waned. All month, buses have zoomed around Washington with Thiem’s face plastered on their sides, the Citi Open touting its acquisition of one of the sport’s brightest up-and-comers.

Thiem is well aware of his status. As the reign of the big four stretches improbably onward, he has grown accustomed to his title as the Next Big Thing. Pair him with the 20-year-old German Alexander Zverev, who beat Djokovic for a title in Rome this year, and the future of men’s tennis may well be at Rock Creek Park this week.

Still, Thiem knows a breakthrough anytime soon is improbable. His past two seasons on clay and Zverev’s win over Djokovic gives him hope that cracks in the ceiling are starting to show, but his expectations remain modest.

“It’s really special, and it’s really unusual that you have four players like this in one generation,” Thiem said. “But I think it’s getting better for the younger players since the past one or two years. There were some tournaments where we had a breakthrough against them — but to win a grand slam or a Masters 1000, you have to usually beat two big-four guys in a row, which is a very tough thing to achieve, and that’s why so little of other players have won the big titles.”

He has plenty examples of that peppered throughout the draw in Washington. On Monday morning, Thiem practiced against Grigor Dimitrov, once dubbed “Little Fed” by fans convinced he could be the next Roger. Juan Martin del Potro, the man who beat Federer in the 2009 U.S. Open final as a 20-year-old, spoke to the media after he did. Both are reminders of what the “Next Big Thing” can become.

For that reason, Thiem keeps his expectations grounded.

“It’s nice to hear,” Thiem said of his and Zverev’s anointment. “But I think we still have to win a lot of matches and win a lot of titles to deserve to be called like that, to be the next big things in tennis. For that, all the other players are still too dominant. It’s nice to hear that, but still I think that’s pretty far away. For both of us.”