Brian Daboll was hired recently to run the offense, which led many to question whether Zorn would be back. He was retained along with assistant head coach Maurice Carthon, tight ends coach Bernie Parmalee, strength coach Mike Clark, wide receivers coach Nick Sirianni and virtually the entire defensive staff.
Jack Bicknell Jr. was hired to coach the offensive line and Jim Bob Cooter was brought in as the offensive quality control coach. Tom McMahon and Derius Swinton will handle special teams.
"We were able to add a handful of strong additions to an already talented group of coaches, and I am excited to get started," Crennel said in a statement issued by the team.
Many believed that Zorn was the front-runner for the offensive coordinator position, but Crennel eventually opted to go with Daboll, whom he coached with in New England.
Besides bringing in a fresh face to run the offense, a new special teams staff and a new offensive line coach to replace the retired Bill Muir, Crennel largely opted for continuity in filling out the rest of his coaching staff.
Linebackers coach Gary Gibbs, defensive line coach Anthony Pleasant, defensive quality control coach Otis Smith, defensive backs coach Emmitt Thomas and defensive assistant Adam Zimmer all worked under Crennel last season, when he was the defensive coordinator for Todd Haley.
Crennel plans to remain the coordinator after assuming the permanent head coaching job.
Parmalee begins his third season in Kansas City, while assistant strength coach Brent Salazar will begin his sixth. Sirianni spent last season as the offensive quality control coach, but will be in his first season as the wide receivers coach.
Bicknell joins the Chiefs after spending the last three seasons as the assistant offensive line coach for the New York Giants, where he just earned a Super Bowl ring. He's also coached in the college ranks at Boston College and Louisiana Tech.
Cooter spent last season with the Dolphins, where Daboll was the offensive coordinator. McMahon and Swinton spent the past three seasons working with the Ram's special teams.
"I'm looking forward to sitting down as a staff, evaluating what we have, what we need and moving forward toward the 2012 season," Crennel said.