(AP) When Serena Williams plays in the U.S. Open semifinals Saturday, her coach, Patrick Mouratoglou, probably will pull out a pen and jot some notes in his black notebook.
He does that at most of her matches, finding things to focus on so Williams can keep improving. Yes, that's right: Williams already owns 16 Grand Slam titles, is ranked No. 1, is three weeks from her 32nd birthday and yet she still wants to get better.
So Mouratoglou and Williams sit together and watch video of her matches, going over the positives and negatives he picked out while courtside.
Says Mouratoglou: "She's working like if she was 19 years old and she wanted to win her first Grand Slam."