Kerrigan, 54, has spent parts of 12 seasons as a Major League pitching coach since first holding the position with the Expos from 1992-96. He took on that role after splitting the previous nine seasons as Montreal's bullpen coach and as a pitching coach in the organization's Minor League system.
It was while with the Expos organization that Kerrigan and Huntington first met, as Huntington joined the organization in 1992.
"I noticed his passion, his knowledge, his attention to detail, his ability to develop young pitchers and at the same time help veteran pitchers improve as well," Huntington said.
In 1997, Kerrigan joined the Red Sox organization, where he served as the team's pitching coach until August 2001. Pedro Martinez captured two of his three Cy Young Awards while working with Kerrigan.
Kerrigan finished out the '01 season as Boston's interim manager, after manager Jimy Williams was dismissed in mid-August. Kerrigan led the club to a 17-26 record to finish out the season, and was replaced by Grady Little for the 2002 season.
From there, Kerrigan moved on to the Phillies organization, serving as the Major League pitching coach for two seasons. He then worked as a special assistant to Yankees GM Brian Cashman in 2005 before taking over as the Yankees' bullpen coach for the 2006-07 seasons.
Kerrigan spent the most recent baseball season working as a radio/TV personality for the Phillies.
As a player, Kerrigan, a right-handed pitcher, split parts of four seasons playing for the Expos and the Orioles.
Kerrigan will take the reins of a relatively young pitching staff that largely underperformed as a group in '08. The starting rotation finished among the league's worst in nearly every statistical category, including at the bottom in ERA (5.36) and wins (33).
Pirates pitchers, as a whole, amassed a 5.08 ERA, the third-worst mark in the Majors, and allowed 657 walks. Only Baltimore issued more free passes.
And, arguably most telling of the staff-wide, season-long struggles, for the first time since 1890, not one Pittsburgh hurler reached 10 wins on the season.
"Joe definitely has a strong entry plan in place for our pitchers," Huntington said. "Part of that will be getting to know each of our pitchers [during the offseason] by either making direct contact with them or breaking down data and getting to know them through film.
"I think the passion that he has for developing young pitchers is going to go a long way."
With Kerrigan, who becomes the Pirates' third pitching coach in as many seasons and the fourth in the past five years, on board, Huntington has just one other Major League coaching vacancy to fill. The organization is still in search of a new first-base coach to replace Lou Frazier.