More than a decade ago, when New Yorkers looked up at the old elevated rail line that traversed the western edge of Greenwich Village and Chelsea, most saw only a rusty, weed-covered eyesore.

But Robert Hammond saw, in the contrast of corroded steel and the burst of wildflowers atop it, an urban kismet — an opportunity for a city amenity like no other. So he became an activist and, in time, co-originator of the High Line, the park in the sky that’s become one of Manhattan’s hottest, hippest oases.

Hammond felt that frisson again Friday when he walked into the Miami Marine Stadium’s grandstand, a rundown relic of muscular concrete overtaken by neglect, graffiti and wild plant growth that some believe could one day be our own High Line-like phenomenon.

“Wow,’’ Hammond said after stepping through a big gap in the chain-link fence around the shuttered stadium and gazing up at its soaring support columns and vast, overhanging roof. “It’s so cool. I really like this style.’’

Hammond wasn’t trespassing. He was invited to lend his moral support and advice, along with a bit of the High Line spotlight, to the long-running campaign to save the stadium.

Friends of Miami Marine Stadium welcomed Hammond at a news conference attended by Miami Mayor Tomás Regalado, a supporter of the effort, and, somewhat incongruously, a large delegation from Miami’s sister city of Kaohsiung, Taiwan, a major center of yacht manufacturing, whose members happened to be in town for the boat show.

Not coincidentally, Hammond’s visit came at a critical moment for the four-year-old marine stadium campaign, which has proceeded in fits and starts. Activists have succeeded in saving the 1963 structure from the wrecking ball, won historic landmark protection for it and generated worldwide admiration for its still-dazzling architecture and engineering.

Leaders of the nonprofit Friends group had hoped to also formally announce an agreement with the city granting the organization the right to undertake the stadium’s renovation, but that has been delayed amid disagreement over details of the deal.

Last year, stadium supporters were ready to walk away in frustration over what they said in a letter were “obstacles’’ imposed by the city, but they now say the deal should be approved soon by the city commission.

The agreement would give the Friends organization, an offshoot of Dade Heritage Trust, two years to raise an estimated $30 million to renovate the stadium, shuttered by the city in 1992 after it was damaged by Hurricane Andrew. Worth said the group has secured more than $10 million of that, including $3 million in public funds.

“The advocacy battle has been won, and we’re at the cusp of the next stage,’’ Friends co-founder Don Worth said. “Now we have to do it.’’

Worth said the High Line project holds telling parallels for the stadium effort: Like the Marine Stadium campaign, it was started by activists with few connections at City Hall, which initially fought it. To stave off the High Line’s demolition, Hammond and his fellow activists had to sue New York City before winning the support of current Mayor Michael Bloomberg.

Friends of the High Line, the organization Hammond co-founded, raised about a third of the $150 million needed to convert the former freight railway and today runs the park, which expanded to a new stretch of the old rail line last year.