After the debacle that was Jim Fassel's final year in 2003, Wellington Mara and the Giants organization decided to bring in Tom Coughlin as their next head coach. Soon after, the player complaints were mounting.
Coughlin and the team started strong in '04, going 5-4 before Kurt Warner was replaced by Eli Manning. The team proceeded to lose six in a row (some in horrid fashion), but Manning and the Giants would win their final game that year against Dallas and head into the offseason with some good thoughts.
The coaching staff assembled around these players also took some lumps, but grew as well. Kevin Gilbride started as the Quarterbacks coach in 2004, and by the end of 2006 had replaced John Hufnagel as Offensive Coordinator.
Offensive Line coach Pat Flaherty was brought on board by Coughlin in January of 2004. He is now in his fifth year and coaches one of the best offensive lines in football. Running backs coach Jerald Ingram is also in his fifth year at his position, and him and Coughlin go all the way back to the 1990s, when he was Coughlin's assistant in Boston College and Jacksonville.
Mike Sullivan has been coaching the Wide Receivers since January of 2004—another guy brought in by Coughlin. The only hold over was Mike Pope, who Coughlin dubbed "The best Tight Ends coach in Football."
Just on Offense, having all these coaches together since 2004 has not only allowed them to get used to each other, but it has given the players the ability to develop relationships and find comfort levels with the coaches—a rare thing in today's NFL where coaches come and go with regularity.
On the defensive side, new Defensive Coordinator Bill Sheridan was hired in 2005 as the Linebackers coach, and new Rams Coach Steve Spagnuolo credited Sheridan with calling a lot of the blitzes the last two years when Spags was the Giants DC. Sheridan came to New York after three years at Michigan under Lloyd Carr.
Secondary Coach Peter Giunta has been with the team since 2006 and was the Rams Defensive Coordinator when they won Super Bowl 34 against the Titans. Dave Merritt works with the Safeties while Giunta works with the Corners and Merritt has been with the team since 2004. One of the only new faces is Jim Herrmann, who worked with Sheridan at Michigan and will serve as the Linebackers coach this year.
Tom Coughlin obviously picked the right group of people, as all but one name mentioned above was hired post Super Bowl 42 victory. The familiarity this group has works both ways, because they have a vast knowledge of their players' skill set and abilities. They also know the tendencies of each other, and each have taken their respective position and turned out solid results.