Notre Dame fired defensive coordinator Brian VanGorder on Sunday, ending a rocky three-year tenure in South Bend.
Greg Hudson, who was on staff as a defensive analyst, was named interim defensive coordinator. VanGorder is the first assistant coach fired by coach Brian Kelly at Notre Dame.
"This is a difficult decision," Kelly said in a statement. "I have the utmost respect for Brian as both a person and football coach, but our defense simply isn't it where it should be and I believe this change is necessary for the best interest of our program and our student-athletes.
"It's never easy to make a change on your staff, but I'm confident in Greg's ability to lead our defense. As a former player at Notre Dame and an experienced defensive coordinator, he not only understands the expectations necessary to compete at the highest level, but he'll bring a fresh perspective to our sideline, practice field and meeting rooms."
The struggles of VanGorder's defense have been at the heart of Notre Dame's 1-3 start to the 2016 season. The Irish allowed 50, 36 and 38 points in losses to Texas, Michigan State and Duke, with the latter one of the program's more embarrassing defeats at Notre Dame Stadium in the Kelly era.
After Week 4, Notre Dame ranks 101st in scoring defense (33.5 points per game), 104th in yards per play allowed (6.18), 93rd in red zone touchdown rate (68.75 percent), 89th in forced turnovers (four), 126th in sacks (one) and 108th in tackles for a loss (17), among other damning statistics.
Even with a host of NFL talent on its roster last season, Notre Dame's defense only ranked 35th in S&P+, which was good enough for the Irish to reach the Fiesta Bowl but not good enough for them to earn a spot in the College Football Playoff.
Hudson was hired as a defensive analyst this year after spending 2013-2015 as Purdue's defensive coordinator. The 1990 Notre Dame graduate also served as a defensive coordinator at East Carolina and Minnesota, and held coaching positions at Florida State (linebackers/assistant head coach, 2010-2012) and Cincinnati (assistant coach, 1997-2000).
"Obviously, this is a difficult day for our coaching staff, but I'm excited and honored about the opportunity that coach Kelly has afforded me," Hudson said. "We've got to improve on defense, without a doubt, and I'm confident that we will. We have great student-athletes and a tremendous defensive coaching staff. I can't wait to get started with our group."