In the final game of the 1984 World Series, Kuntz hit a pop fly to the second baseman that became the deciding run batted in (RBI).

He went to the Division III World Series twice with California State University, Stanislaus before being selected by the White Sox in the 11th round of the 1977 Major League Baseball draft.

Since his playing career ended, Kuntz has worked with several MLB organizations, including the Houston Astros, Seattle Mariners, Florida Marlins, Kansas City Royals, Atlanta Braves and Pittsburgh Pirates.

From 2012 to 2017, he served as the first base coach for the Kansas City Royals, and has received substantial praise for his contributions to the team's success during that period.

[3] He hit .263 for Knoxville with 10 home runs in 113 games; the team was managed by Tony La Russa for part of the season and won first place in the Southern League.

[3] He was traded to the Minnesota Twins in June 1983, with the White Sox receiving minor leaguer Mike Sodders in exchange.

[11] The Pashnick-Kuntz trade was prompted because future Baseball Hall of Fame outfielder Kirby Puckett was playing in the minor leagues for Minnesota's Class AA affiliate and was expected to quickly join the Twins as an impact player.

[2] In the fifth and deciding game of the 1984 World Series against the San Diego Padres, Kuntz pinch-hit for designated hitter Johnny Grubb with the bases loaded and the score tied at three.

Kuntz hit a pop-up to short right field that Tony Gwynn was unable to see ("I lost it in the sky," he admitted in a radio interview years later).

Second baseman Alan Wiggins made the catch, but was unable to prevent Kirk Gibson from racing home from third with the go-ahead run.

[2] In a 2010 Baseball Prospectus article, Steven Goldman wrote that the 1984 Tigers were "a great team that relied on a lot of fluke elements...

The club made up for this in part by getting terrific production out of role players like Ruppert Jones, Johnny Grubb, and Rusty Kuntz, players who wouldn't synch up again..."[12] Kuntz returned to the Tigers in 1985 but appeared in just five games (last on April 24, 1985) before being sent back to the minor leagues.

[3] Kuntz retired as a player with 277 games played, a .236 career batting average, 5 home runs and 38 RBI.

In August of that year he worked on defensive skills with Gary Sheffield when the major league slugger was struggling with injuries.

At that time, Marlins players including Cliff Floyd and Mark Kotsay praised Kuntz for the amount of preparation that he put into his coaching.

The move was part of a mass firing of Marlins personnel in player development and scouting after the team's change in ownership.

Kuntz, who was paid for the 2002 season in any case due to the terms of his contract, kept a job working on the grounds crew at the team's spring training site.

[17] In October 2005, the Pirates offered minor league positions to Kuntz and fellow coaches Gerald Perry and Alvaro Espinoza.

[23] In a January 2014 article, the Boston Globe listed Kuntz as one of the baserunning/outfield coaches who had the most respect among his peers in the major leagues.

[24] For the 2018 season, the Royals announced that Kuntz will be moved to another role in the organization and he will not return to his original position as first base coach, being replaced by Mitch Maier.

"[32] In April 2013, The Big Lead published a post about the name after a photo depicted Kuntz standing to the right of White Sox first baseman Paul Konerko and Royals baserunner Chris Getz.