 In the 1950s, Giants' owner Horace Stoneham began to consider moving the team to another city while needing a new stadium to replace the crumbling Polo Grounds.San Francisco mayor George Christopher negotiated with Stoneham, approving the move to San Francisco starting with the 1958 season.The approval caused the upset Giants fans to storm the field during the last home game before the relocation, stealing the Eddie Grant plaque and losing the team identity.