Moving a Grand Slam event into its qualifying week takes the biggest tournaments in tennis into unexplored territory.

The U.S. Open's plan to make its mixed doubles championship a smaller, shorter event aimed at persuading top singles players to compete was criticized Tuesday by doubles specialists who figure to get shut out of the new format.

The U.S. Open mixed doubles competition will now be played before the singles main draw, the United States Tennis Association (USTA) said on Tuesday as it announced an overhaul of the category's format and an increase in prize money.