Roger Federer, comparing his play now to during his dominant years between 2004 and 2007, says he is doing some things better but does not have the same confidence.
"So much time has gone by and I've practiced so hard over the years, that I feel I have more power on my serve. I volley better now, I guess," said the 33-year-old Swiss after reaching the U.S. Open fourth round for the 14th straight year. "I've gotten to understand so many things over those years. But the thing back then is I was so unbelievably confident. I was coming through stretches where I wouldn't lose against Top 10 players. I wouldn't lose finals.
"I had an unbelievable winner mentality. Not that I don't have it today, but I haven't won as much as I did back then. I think that could make a difference. Otherwise I'm very pleased with how things are going this year."
From 2004-07, Federer won 42 titles, including 11 Grand Slams. Since then he's won 26 titles, including five Grand Slams.
Federer also noted that he has regained his movement following back problems a year ago. "I think especially now it's been really excellent the last three matches here at the U.S. Open," he said. "The coordination is there, as well. I feel like I've gotten used to the hard courts by now. It's really working well. I'm very pleased."
Training and fitness were the keys, he emphasized, saying, "I think when you keep yourself in shape and train the right way, that's how you do it. Then actually it's not such a surprise for yourself. But I'm clearly happy about it because it's become a game of movement."
Federer has won three titles this season and returned to No. 3 in the rankings.