A 6-foot-1, 240-pound pass rusher, the younger Mack posted eight sacks at Buffalo in 2019. He also forced three fumbles, a staple of his older brother.
The Bears' other signings were Mississippi State defensive lineman Lee Autry, Yale offensive lineman Dieter Eiselen, Maryland inside linebacker Keandre Jones, Western Illinois outside linebacker LaCale London, Florida International running back Napoleon Maxwell, Duke defensive lineman Trevon McSwain, Oregon State running back Artavis Pierce, Florida Atlantic inside linebacker Rashad Smith, LSU offensive lineman Badara Traore and Kentucky receiver Ahmad Wagner, who previously played basketball at Iowa before switching to football for the past two years.
With NFL offseason programs currently prohibiting on-field work due to the coronavirus pandemic, it's uncertain when a rookie minicamp could be held.