The Cowboys placed rookie first-round LB Malachi Lawrence on injured reserve and activated OLB Marist Liufau from injured reserve, according to Adam Schefter of ESPN and Mike Garafolo of NFL Network.
Lawrence has a high ankle sprain, according to Todd Archer. Lawrence had moved into the starting lineup three weeks ago, while Liufau missed the first eight games with a fractured forearm suffered in the preseason, Archer added.