Agnieszka Radwanska may be just 24, but she already feels like an old hand on tour.
And perhaps it is no surprise, after all 2013 was remarkably the World No.5's ninth full season on tour. It was also the sixth time in the last seven years that she has played in excess of 60 matches - an impressive, if exhausting, statistic.
"I mean, I'm not feeling so young anymore, especially with my body after all those matches in the last few years," Radwanska said during the recent WTA Championships in Istanbul.
"There are a lot of 16 and 17-year-old girls that are playing really, really good tennis. I think this year there are a couple of names that we are going to see more often in the future," she added. "I will be 25 soon, so I think I'm not young anymore."
Behind the peerless Serena Williams, Radwanska led the WTA this season in terms of matches played (75) and won (56), a level of consistency that she was understandably delighted with.
"I think it was a good year," she said. "You know, I'm still in the Top 5 and I'm very happy about that. I really played consistent tennis pretty much the whole year and even made the quarterfinal of a Grand Slam on the clay.
"Of course, I had some tough losses as well this year, but altogether I would say it's a good year."
And she is already looking forward to the next. Although before then she is taking the chance to get a well-deserved break from the court.
"Well, of course, tennis is always the priority, and even in the off-season the practice always comes first," she said. "You're doing everything to be the best you can but the off-season is the time when on the weekend you can go out and you can go party.
"So, you know, I'm very happy that I can have a long break, but on the other hand it's two months and after three weeks it's almost December and you already have to start getting ready for the Australian Open!"