NEW YORK, September 2 (Reuters) - Maria Sharapova has shrugged off Caroline Wozniacki's criticism of U.S. Open organisers for giving the Russian centre court billing in her return to grand slam tennis after a doping ban. Defeated by Ekaterina Makarova on an outside court in the second round, former world number one Wozniacki lashed organisers for scheduling Sharapova at Arthur Ashe Stadium in her opening matches. Sharapova, who returned from a 15-month ban in April, was handed a wildcard for the year's final grand slam and made her third consecutive appearance in the main stadium on Friday, beating American teenager Sofia Kenin 7-5 6-2 to reach the fourth round.