>>> U.S. OPEN CONTINUES TODAY IN NEW YORK CITY WITH SOME OF THE BIGGEST STARS IN TENNIS PLAYING THEIR FIRST MATCH OF THE TOURNAMENT. THEY EACH PLAY IN HOPES OF ADDING ANOTHER GRAND SLAM TO RESUMES. COCO GAUFF GOT OFF TO A GREAT START AT DEFENDING HER TITLE, BEAT OPPONENT IN STRAIGHT SETS AND WILL PLAY SECOND ROUND MATCH TOMORROW. DEFENDING CHAMPION NOVAK DJOKOVIC ALSO ADVANCED WITH A STRAIGHT SETS VICTORY. HE IS IN PURSUIT OF HIS FIFTH TITLE. I BRING IN SENIOR WRITER THAT COVERS TENNIS FOR THE ATHLETIC. THANKS FOR JOINING US. EXCITING TIMES IF YOU ARE INTO TENNIS FOR SURE. SLOAN STEVENS LOST AFTER HAVING MATCH POINT TWICE. WHAT WENT WRONG FOR THE FORMER U.S. OPEN CHAMPION? >> THANKS FOR HAVING ME, ANNE- MARIE. GOOD MORNING. IT WAS A REALLY TOUGH NIGHT. I MEAN, SHE WAS ABSOLUTELY ON CRUISE CONTROL, UP 6-LOVE, 3-0. TENNIS IS JUST ONE OF THE SPORTS WHERE YOU CAN'T RUN OUT THE CLOCK. YOU HAVE TO WIN THE FINAL POINT. THAT'S ESSENTIALLY WHAT HAPPENED TO SLOAN STEVENS. THE SORT OF FREEZING UP AS THAT SORT OF TEST GOT CLOSER AND HER OPPONENT REALLY PICKED UP HER GAME. IT WAS JUST SORT OF LIKE WATCHING A CAR ACCIDENT HAPPENING IN REALTIME AS THAT NEXT SET AND A HALF UNFOLDED. >> LET ME ASK ABOUT SOMETHING ELSE. THE NUMBER ONE SEED HAS BEEN AT THE CENTER OF A DOPING CONTROVERSY. CAN YOU WALK US THROUGH THE SITUATION AND WHAT HIS COMPETITORS ARE SAYING AHEAD OF HIS FIRST MATCH TODAY. >> IN MARCH HE TESTED POSITIVE TWICE FOR A STEROID. THAT IS AN OLD CRUDE STEROID THAT NOBODY USES ANYMORE. WHEN TESTERS DETECT THAT, WHAT IT USUALLY MEANS IS AN ATHLETE HAS USED AN OVER THE COUNTER PRODUCT THAT CONTAINS IT. THEY FOUND A TINY AMOUNT. THIS IS SUCH A SMALL AMOUNT THAT IT COULDN'T HAVE AN EFFECT ON HIM. IS IT A SIGNAL THAT HE IS USING OTHER STEROIDS OR USING THAT STEROID IN A LARGER QUANTITY AND IT PASSED THROUGH HIS BODY? SOME OF THE MOST STRINGENT DOPING TESTERS IN THE WORLD RULED THAT WASN'T A POSSIBILITY. THIS IS SORT OF HARD FOR A LOT OF PEOPLE WHO DON'T UNDERSTAND THE SCIENCE AND DON'T UNDERSTAND SORT OF UP TO DATE DOPING TESTING PROCEDURES TO ACCEPT BECAUSE, YOU KNOW, THEY SEE DOPING AND THINK IT'S BARRY BONDS, THINK IT'S ALL LANCE ARMSTRONG, AND IT'S NOT. IN THIS CASE IT IS VERY EMBARRASSING FOR SINNER. HE WOULDN'T HAVE WANTED IT THIS WAY. OPPONENTS SAY IT RAISES SUSPICIONS. BUT THE DOPING POLICE, THE PEOPLE REALLY HARD ON PEOPLE ABOUT THESE THINGS, AND THAT'S THEIR JOB, THEY HAVE CLEARED HIM AND I THINK