Tomas Berdych claims the era of tennis being about the 'big four' is coming to an end with other players now coming into contention.
The 32-year-old Czech, who is preparing to get his 2018 campaign under way at the Qatar Open, was discussing how tennis has been dominated by Roger Federer, Novak Djokovic, Rafael Nadal and Andy Murray over the past seven years with the quartet claiming 28 of 32 Grand Slam titles since 2010.
Berdych feels that there is now an emerging crop of other players who will be coming to the fore to challenge those four stand-out names, especially as Murray and Djokovic have not featured since the middle of 2017 because of respective injury problems.
When asked if the 'big four' era was all but over, the world number 16 said: "It's hard to say right now. But yes, I think it's very possible.
"I'm not saying that it's over, but I think it's the nature of the process of the time and of the sport."
Meanwhile, Berdych is not giving up hope of winning a Grand Slam before he retires, despite his only final appearance coming at Wimbledon back in 2010.
He added: "I think that's the beauty of our sport that no matter where you are, you still have a big chance.
"It's about that particular day, and from that one day you can create a great week. From one great week, you can make it two and that's what you are looking for.
"To be honest, that's the only reason why I'm still around."