Larry Roberts occasionally drives by a barren plot of land in Pentagon City. Amid the open fields and warehouses, he hears the crack of a bat against a ball and sees 40,000 fans cheering on a beautiful summer night as they look out over the Washington Monument.

"It's hard to get it out of your mind," says Roberts, who helped lead Arlington's aborted bid for a Major League Baseball team. "It just makes me heartsick to think of what could have been. It's an incredible lost opportunity for Arlington."

County Board member Paul Ferguson (D) visualizes something entirely different for the same 10-acre plot of land: a sparkling new conference center that would be a prime source of tax dollars. As for the effort to bring baseball to the county, he sees a well-intentioned campaign that foundered because backers never had a concrete site for a stadium, much less a promise that there would be a team to play in it.

"It was not a matter of whether baseball was a good or bad thing," said Ferguson, who was chairman when the board requested that the county be withdrawn from consideration for a team. "It was whether the proponents had a realistic proposal."

As the one-year anniversary of Arlington's decision to pull out of the baseball sweepstakes passed this week and as Major League Baseball says it is nearing a decision on where to locate a team, people involved in the bitter debate in Arlington looked back with mixed feelings. Proponents expressed regret that Virginia's only chance of landing a team is now in outlying Loudoun County, even as they credited opponents of an Arlington stadium with running a well-organized campaign.

They maintain that Arlington, with its proximity to the District and accessibility to the rest of Northern Virginia, would have been the perfect place for a stadium, which backers think would have boosted development and stirred community pride.

"Everything was here: the two Metro stops, the views of D.C.," said Richard K. Kelsey, who last year ran unsuccessfully for the County Board on a pro-baseball platform. "It was the best of both worlds."

But opponents are unbowed. "The only missed opportunity was the opportunity to have more traffic and more congestion," said Sarah Summerville, who headed a group called Arlingtonians for Baseball in D.C. and is credited by both sides with organizing the strong grass-roots opposition to a stadium in Arlington.

"We were looking at placing a 42,000-seat stadium on a city block right in Crystal City, with afternoon and evening games and fans traveling to games at rush hour," Summerville said. "We don't have the infrastructure to support that. It made no sense, it was not logical and it was not something that the community wanted."

The debate about baseball in Northern Virginia arose from the planned move of the Montreal Expos. In March 2003, Virginia officials made public five possible sites for a stadium to land the team.

Three of them were in Arlington County: the 10-acre plot in Pentagon City; a nearby site at the Costco complex next to the Fashion Centre at Pentagon City; and a site in Rosslyn near the River Place apartment complex. The other two sites in Northern Virginia were just east of Dulles International Airport next to the Center for Innovative Technology and in Springfield, on surplus Army land at Fort Belvoir.

The Virginia ballpark was to include an expansive green space beyond the playing field where about 8,000 fans could watch the game while picnicking or strolling through a memorial park. The stadium was projected to include about 25,000 square feet of retail space and, if located in Arlington, was to connect to the planned county conference center.

Stadium proponents mounted a campaign, attending everything from Little League parades and County Board meetings to spread their message. But opponents, who included Summerville's group and several local civic associations, mounted what both sides now agree was a more intense and organized effort that included e-mails, newsletters and community meetings.

"We were running a very positive but very soft campaign. They were running a scorched-earth campaign," said Brian Hannigan, a spokesman for the Virginia Baseball Stadium Authority, the state-created entity pushing for a Virginia team.

He blamed local politics for the county's decision to pull out, which he termed "a tragedy," and said opponents had "blatant disregard for the facts" of the economic and other benefits baseball could bring.

On July 18 of last year, Ferguson sent a letter to the authority saying the board had decided that the county should be taken off the list of potential sites. While commending baseball backers for mounting an "enthusiastic" campaign, the letter said the issue was dividing the community and that Major League Baseball was moving too slowly with its decision. The letter added that a mixed-use development, such as the planned conference center, would provide greater revenue for the county.

In an interview, Ferguson said the debate was frustrating because plans for a stadium never advanced beyond a "hypothetical concept. The baseball advocates had no contract ownership or lease for a property in Arlington. They were only picking out sites they would like to have."

He contrasted that with the Dulles site in Loudoun County, where developers would supply land for a stadium and build a massive parking lot, along with 5,400 condominiums or apartments, more than 850 single-family homes and 5 million square feet of commercial space around the ballpark.

The Dulles site is now Northern Virginia's only contender. It is competing with the District, which has identified four potential sites, along with Norfolk, Las Vegas, Portland, Ore., and Monterrey, Mexico.

Looking back, some proponents say they blame the unwillingness of Major League Baseball to make a decision more than they blame their elected officials.

"We were undermined by baseball not being willing to put its cards on the table at a time when the board was being asked to make a politically difficult choice," said Roberts, co-chairman of the Arlington Baseball Coalition. He expressed skepticism about baseball's recent announcement that it would make a decision sometime after last week's All-Star Game.

"The question is which all-star game," Roberts said.

One lingering frustration for stadium proponents is that one year later, the planned conference center remains in limbo, with even Ferguson acknowledging that "it may very well not work out."

County officials said negotiations continue with the property owner.

Kevin Lewis, 6, and a group of stadium advocates show their support for baseball in Arlington outside the County Board office last July.