The sale of the Washington Nationals appeared to be accelerating yesterday when Major League Baseball delivered highly detailed purchase agreements to the eight groups bidding on the team, according to sources involved in the process.

Purchase agreements are legal documents that specify exactly what is being bought and sold, similar to a contract purchasers sign when they agree to buy a house. If the document is signed and returned to baseball, the bidder is officially agreeing to pay a certain price for the team, according to sources.

Baseball presumably will select a bidder once the purchase agreements are returned. Several bidders, who spoke on the condition they not be identified for fear of hurting their chances, said the league did not specify a deadline for the return of the documents.

Baseball also requested yesterday that each group submit its partnership agreement, which identifies the investors in each group and the "control person" who would run the Nationals and represent the team at baseball meetings.

The purchase agreements come on the heels of other financial documents that each bidder filed with baseball on Monday, specifying the amount they intend to pay for the Nationals and how they plan to pay, among other information.

Most of the groups are believed to have bid in the $450 million range for the Nationals, who are owned by MLB.

Also yesterday, in further evidence that baseball is trying to complete the Nationals' sale, league representatives met with District officials in an attempt to complete a lease covering the Nationals' use of a $535 million, city-built stadium set to open in 2008. Baseball has said it wants a lease agreement with the city in place before it selects a new owner.

None of the eight bidders had been eliminated as of yesterday, according to baseball officials. It is difficult to pinpoint a front-runner, although Indianapolis media mogul Jeffrey Smulyan has intensified his efforts lately, recruiting several Washington-based investors. But several other bidders are believed to be in the hunt as well, including the Lerner family, which leads a Bethesda-based real estate empire; a local syndicate led by businessmen Frederic Malek and Jeffrey Zeints, who are favored by D.C. Mayor Anthony Williams; and Atlanta-based sports executive Stan Kasten.

Other still in the running include Chicago businessman Yusef Jackson, who has teamed with billionaire investor Ronald Burkle of California; Franklin Haney Sr., who has developed several Washington area projects; local entrepreneur Jonathan Ledecky, who has teamed with billionaire George Soros; and a group headed by Sallie Mae Chairman Albert Lord and Virginia businessman William Collins.

Baseball is trying to complete the sale by the end of the month to give the new owners enough time to put together their own staff and players in time for the 2006 season.