Gore rejected an outright assignment to Triple-A Syracuse and elected free agency Thursday, Tim Healey of Newsday reports.
Gore pinch ran and stole a base and scored a run in a 7-3 win Sunday over the Pirates.
Gore had his contract selected by the Mets on Wednesday, Tim Healey of Newsday reports.
Gore signed a minor-league contract with the Mets on Wednesday, Jacob Resnick of MLB Pipeline reports.
Gore was outrighted to Triple-A Gwinnett on Saturday.
Gore was added to Atlanta's World Series roster Tuesday, Kiley McDaniel of ESPN.com reports.
Gore has been left off Atlanta's roster for the NLCS against the Dodgers.
Gore was included on Atlanta's roster for the NLDS against the Brewers.
Gore signed a minor-league contract with Atlanta in mid-February.
The Dodgers declared Gore a free agent Sunday, Eric Stephen of SBNation.com reports.