Over on the Diamondbacks' side, we have Evan Longoria who played for the Giants from 2018-2022. While he wasn't anywhere near as good with San Francisco as he was with the Rays early in his career, Longo still put up a reasonable .251/.312/.438 with the Giants while being a solid defender at third. The Giants declined his option after the 2022 season and Arizona picked him up on a one year, $4 million contract for this season where he saw limited playing time in the regular season, but has since become a key cog of the Diamondbacks' offense this postseason.
We won't be seeing Madison Bumgarner pitching in the World Series this year as he was released by the Diamondbacks back in April, but he still played (poorly) for Arizona in 2023 and would be in line to get a ring if the Diamondbacks can pull it off. Bumgarner needs no introduction to Giants' fans as he won three World Series rings, made four All-Star teams, and cemented his status as one of the best postseason pitchers of all-time during his tenure with the Giants.
Melancon is another name that could get to lay claim to the title of World Series Champion that won't be playing for the Diamondbacks in the series as a shoulder injury has kept him out for the entire 2023 season. However, he is a member of the Arizona Diamondbacks which is the NINTH team he has played for in his career. His best days as a reliever were with Pittsburgh where he was one of the best bullpen arms in baseball, but he was still a very solid reliever in San Francisco from 2017 until the Giants' traded him to the Braves at the 2019 trade deadline.