Ohio State announced former Michigan defensive line coach Greg Mattison and former San Francisco 49ers defensive backs coach Jeff Hafley will join the coaching staff as co-defensive coordinators.
Since 2015, Mattison has served as the defensive line coach for the Wolverines, a line that helped allow opponents to average 3.7 yards per carry and opposing quarterbacks to complete 49.5 percent of passes attempted, No. 1 in the Big Ten. Mattison also served as a defensive coordinator for Michigan from 2011-14.
Hafley has been a defensive backs coach at the pro level since 2011, coaching for the Tampa Bay Buccaneers, the Cleveland Browns and the 49ers.
The press release listed that Hafley and Mattison join defensive line coach Larry Johnson, who has been named as the associate head coach under head coach Ryan Day, as the only members of the Ohio State coaching staff. The release failed to mention defensive coordinator Greg Schiano, cornerbacks coach Taver Johnson and linebackers coach Billy Davis.