In a Dec. 28 letter sent to 49ers owner John York, Newsom promoted the site as a spacious, accessible alternative to the team's current home at Candlestick Point. A new stadium at Hunters Point also would bring needed jobs to the economically depressed neighborhood nearby, Newsom wrote.

The 49ers responded skeptically to the proposal, with York on Tuesday accusing Newsom of "political gamesmanship" and expressing doubts about the polluted site, which the team has rejected before.

An study of Hunters Point by the 49ers about two years ago raised concerns about the site's distance from freeways and the U.S. Navy's timeframe for cleaning up hazardous waste there, York wrote in a letter responding to the mayor.

"While we thought the site had potential, we ranked it well below a number of other sites in the Bay Area," York wrote.

The 49ers announced in November they had abandoned a decade-long attempt to build a stadium at Candlestick Point, its San Francisco home since 1971, and planned to move to the town of Santa Clara south of the city.

York's wife and 49ers co-owner Denise DeBartolo York said last week the Santa Clara site had received the blessing of NFL Commissioner Roger Goodell during a fall visit.

But NFL spokesman Greg Aiello said Wednesday the commissioner "has not made any determination on where the stadium should be."

John York also lashed out at an opinion piece Newsom published in the San Francisco Chronicle last month exhorting the team to keep its "promise to us" to build a stadium that would anchor the economic revitalization of the city's Bayview District.

"The assertion that the 49ers are responsible for the lack of economic progress in the Bayview is not only wrong, it is offensive," York wrote.

In a quick response issued Tuesday, Newsom wrote he was "unapologetic" about his commitment to the Bayview.