U.S. tennis chiefs announced a radical overhaul of the U.S. Open's mixed doubles on Tuesday, unveiling plans to stage the competition as a standalone event in the week before the main men's and women's singles draws get under way.

In a dramatic move that was greeted with criticism in some quarters, U.S. Open organizers said the mixed doubles event, using an amended rulebook, would now take place over two days of competition on Aug. 19 and 20 at Flushing Meadows in New York.

The tournament will be made up of 16 teams, with eight teams earning direct entry based on their combined singles ranking playing alongside eight wild-card entrants.