In a surprising new admission, Boston Mayor Martin J. Walsh says he tried to revive the Grand Prix of Boston days after the race collapsed amid a firestorm of finger-pointing between the promoter and City Hall.

Walsh, in an interview with the Herald, confirmed what his press office has vehemently denied — that he huddled with Grand Prix CEO John Casey nearly a week after Casey abruptly cancelled the race, in a last-ditch attempt to move the IndyCar course to the Suffolk Downs racetrack.

“We had a meeting trying to see if we could salvage the race,” Walsh told the Herald. “Suffolk was open to having a conversation about it.”

Asked why he would continue to work with Casey after the promoter blew up the race and compared his dealings with the Walsh administration to an “abusive relationship,” the mayor said: “At that point there were a lot of tickets sold and I still felt it would be a good draw (for the city).”

Walsh said he called former state Sen. Anthony Petruccelli of East Boston to see if Suffolk Downs would consider holding the IndyCar race. Casey even flew his course designer Tony Cotman to Boston to scope out the race track.

The Suffolk Downs plan — reported by the Herald at the time — died when IndyCar CEO Mark Miles refused to move the race out of city streets and said he wouldn’t work with Casey anymore.

It turns out Suffolk Downs may not have been the best choice because the property also lies within new flood zone restrictions — the same problem that helped kill the original race course in the Seaport District.

Walsh has been blamed by critics for killing the race, but in fact he went to extraordinary lengths to save it — an effort that now looks foolhardy given the numerous lawsuits targeting Casey for bankrupting the Grand Prix, owing millions of dollars to ticket holders, vendors and sponsors.

The Herald reported last week that Casey said he has talked to the U.S. Attorney’s office about his dealings with the city and that investigators have now expanded their probe of City Hall and union tactics to include the Grand Prix.

A Walsh spokeswoman denied any city officials have been interviewed about the Grand Prix and criticized the Herald for reporting Casey’s claims.

Walsh’s new comments to the Herald came after IndyCar filed a new complaint against Casey yesterday, charging him with fraud for filing false financial statements he used to personally guarantee the race.

The complaint also revealed the previously unknown May 5 meeting attended by Walsh, Casey, chief of staff Dan Koh, other city officials and an IndyCar official.

The mayor’s eleventh-hour attempts to salvage the race have never been acknowledged by the city. After the Herald reported on its website on May 5 that Casey had attempted to shift the course to Suffolk Downs, a Walsh spokeswoman told the Herald the story was false and should be corrected, saying: “On the record, there is no truth to that.”

In another development yesterday in the Grand Prix fallout, the Massachusetts Convention Center Authority filed a claim in federal bankruptcy court for nearly $1 million from the defunct Grand Prix. That amount includes the license fees the authority would have gotten from holding the IndyCar event on Labor Day weekend as well as other unpaid invoices.