The Boston Redevelopment Authority’s controversial deal to hand over Yawkey Way to Red Sox owner John Henry and his partners by declaring Fenway a blighted area is a “sitting duck” for a lawsuit, experts said as the inspector general and attorney general review the pact.

“If they say that it’s a blighted area, that’s preposterous,” said Herbert Gleason, a development attorney and head of the city’s law department under former Mayor Kevin H. White. “I think the taking is invalid and only the City Council and the mayor can agree to whatever the terms are to the disposition of the property. It could be open to a ‘10-taxpayer’ suit. I think it would be a sitting duck.”

Under state law, any 10 taxpayers can ask for the courts to intervene on government decisions on behalf of the citizens.

Gleason called the behind-the-scenes deal a “work-around” to avoid a City Council vote on the $7.3 million plan to give the Red Sox game-day and event concessions on Yawkey Way, as well as air rights for Green Monster seats on Lansdowne Street for as long as the team plays in Fenway.

“The city charter requires the sale and leases of city property to be approved by the City Council,” Gleason said.

The BRA took easement rights to Yawkey Way last month in order “to protect against or eliminate ‘urban blight,’” according to paperwork the agency quietly filed with the Suffolk County Registry of Deeds on Oct. 23 — on the same day as Game 1 of the World Series.

“I hope that a 10-taxpayer lawsuit is filed,” said Gregory W. Sullivan, research director at the Pioneer Institute and former state inspector general. “The courts have said these takings have to be related to a public purpose, and the idea that Yawkey Way is a blighted area during Red Sox games is the equivalent to saying Faneuil Hall is a blighted area during Fourth of July weekend.”

Sullivan also accused the BRA of sidestepping bidding laws.

“This is biggest sweetheart deal that I have ever seen in my 30 years in government. The curtain is coming down on the Menino administration, and the developers are diving under the curtain before the new mayor comes in,” said Sullivan, who questioned the BRA’s authority to negotiate the deal with the Red Sox last year while he still served as IG. “Had it not been for this ruse of a taking as a blighted area, it would have had to be bid. I think the attorney general’s office should step in on this.”

State Inspector General Glenn A. Cunha, who is also probing the deal, has criticized the BRA for failing to hold public hearings or seek a formal, written appraisal of the land.

The AG’s office is also reviewing the matter, said spokesman Brad Puffer.

The Red Sox refer all questions about the deal to the BRA, which defended it as well as the move to label the area surrounding Fenway as blighted.

“With access to Yawkey Way, Fenway Park can continue to be a 21st century urban ballpark and a catalyst of economic development in the Fenway neighborhood,” said BRA spokeswoman Melina Schuler. “The 2000 blight finding by the state Legislature regarding Fenway Park remains in place, and the recent extension of the experiment started 10 years ago signals that the commitment the Red Sox are making to Fenway Park projects and improvements are now secure.”