U.S. coach Jurgen Klinsmann intends to call a full complement of 30 players for his team's pre-World Cup training camp at Stanford University.
Klinsmann plans to announce his preliminary roster May 12, a day before it must be given to FIFA and two days before the training camp opens. He must submit a final 23-man roster to FIFA by June 2.
He said some players who are coming back from injuries need to be evaluated.
Preparing for their seventh straight World Cup appearance, the Americans play exhibitions against Azerbaijan on May 27 at San Francisco; Turkey on June 1 at Harrison, New Jersey; and Nigeria on June 7 at Jacksonville, Florida.
They travel the following day to their their base camp in Sao Paulo. At the World Cup they open against Ghana on June 16 at Natal, face Cristiano Ronaldo's Portugal six days later in the Amazon rain forest city of Manaus and close the group stage against Germany on June 26 at Recife.