What to watch at Open: Will Sharapova foe take TO?FILE - In this June 15, 2014, file photo, Grigor Dimitrov, of Bulgaria, poses with the trophy after his win against Feliciano Lopez, of Spain, at the end of their Queen's Club grass court championships singles final tennis match in London Heading into the U.S. Open, Roger Federer, Rafael Nadal, Novak Djokovic and Andy Murray have won 36 of the past 38 Grand Slam titles, a stretch dating to the 2005 French Open. Nowadays, there seems to be a growing sense _ or hope, maybe _ among the best of the rest on the men's tennis tour that the quartet might be more vulnerable than ever. (AP Photo/Sang Tan, File)
NEW YORK (AP) -- If Maria Sharapova's opponent Wednesday at the U.S. Open takes a medical timeout, the five-time major champion wouldn't mind seeing that come at a cost.
Sharapova was asked after her first-round victory at Flushing Meadows what tennis rule she would like to change if she ran the sport, and - tongue-in-cheek - she mentioned charging for breaks players are allowed to take to get a visit from a doctor during a match.
''I think we'd all see who really uses them and who doesn't,'' said 2006 U.S. Open champion Sharapova, who faces Alexandra Dulgheru in Arthur Ashe Stadium in the second round. ''I don't know what we put on it - maybe like $2,500 or something. Yeah, I think we should do that. That would be fun.''
Here are some other things to watch on Day 3 at the U.S. Open:
DIMITROV WANTS MORE: For years, Grigor Dimitrov has been pegged as the next big thing in men's tennis. He even got tagged with a nickname, ''Baby Fed,'' that attached his potential to the prowess of Roger Federer.
Dimitrov, 23, reached his first Grand Slam semifinal at Wimbledon last month, before losing in that round to eventual champion Novak Djokovic.
Now Dimitrov, who begins his U.S. Open by facing Ryan Harrison of the United States on Wednesday, wants more.
''I'm happy to be at that stage,'' the seventh-seeded Dimitrov said, ''but now my ultimate goal is to get even higher: Why not win a Slam?''
VENUS WANTS DOUBLES TITLE, TOO: Two of Venus Williams' seven Grand Slam singles trophies came at the U.S. Open, but she hasn't been past the second round in New York since 2010.
She can get to the third round by beating Timea Bacsinszky of Switzerland on Wednesday.
The 34-year-old American also is entered in doubles with her younger sister Serena. They have won 13 Grand Slam doubles titles as a team, and the older Williams was asked whether she might consider dropping out of doubles in order to focus on - and save energy for - singles.
''I don't think that's wise, because the doubles is a title. When they say your name and they say so-and-so has X number of titles, guess what? Those doubles ones feel real good,'' Williams said. ''For me, the doubles is very serious. It's not, 'Oh, let's play for fun.' Those are Grand Slam titles that I am trying to win. So I never would withdraw from a Grand Slam competition, singles or doubles, lightheartedly.''
WHAT WILL GULBIS DO?: Anything is liable to happen when Latvia's Ernests Gulbis is on a court.
He's a volatile sort who takes pride in the number of rackets he breaks during matches.
He also is capable of sublime tennis, such as when he beat Roger Federer en route to the semifinals at the French Open in June. And equally liable to bow out of a tournament early, such as his second-round loss at Wimbledon later that month - or his exits in the first or second round at every U.S. Open since 2008.
So it's always a good idea to keep an eye on the 11th-seeded Gulbis, who meets Kenny De Schepper of France in the Grandstand in a first-round match.
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