Despite holding wins over Grand Slam champions, Dominic Thiem believes he and the next generation are still a long way off the traditional Big Four.
The 23-year-old Austrian defeated Rafael Nadal in the Italian Open as well as Novak Djokovic in the quarter-final of the French Open this year as he currently ranks at a career-high world number seven.
Meanwhile, another young prospect in world number eight Alexander Zverev also defeated Djokovic to win the final in Rome earlier this year.
However, the duo and other young stars such as Nick Kyrgios are still miles away from being called the next big things in tennis according to Thiem.
"We still have to win a lot of matches to deserve to be called the next big things in tennis," Thiem said, as quoted on Yahoo. "It's nice to hear that but I think it's still a pretty long ways for both of us."
The other two members of the Big Four are of course, current Wimbledon champion Roger Federer and Andy Murray as no tennis player has won at SW19 other than the four players since Lleyton Hewitt accomplished the feat in 2002.
Having dominated tennis for over a decade, Thiem believes the Big Four's decreased participation in tournaments in recent times can only help upcoming players.
"They are really special," he added. "It's very unusual you have four players like this in one generation. I think it's getting a little better for the other players. They are starting to take a few tournaments. In the Grand Slams you would have to beat two or three (of them) in a run. That's why other players haven't won the big titles."
With the US Open approaching this month, Thiem has cited the importance of a strong run heading into the final Grand Slam of the year as he takes part in the Washington Open.
"It's important to find a strong game. It's the start of a very long journey," Thiem explained. "I hope it works out well here in Washington. We have a lot of tough matches ahead. From round one basically there are only really tough matches."
"Of course it's nice to be top seed here [in Washington] but it doesn't affect anything because the guys behind me are really strong."
The US Open commences on 28 August.