The NFL suspended free agent defensive lineman Robert Nkemdiche for two weeks, Field Yates of ESPN reports.
The violation of NFL rules was not disclosed.
The Dolphins cut Nkemdiche last week. He played two games but had no statistics while seeing action on 17 offensive plays and 11 on special teams.
Miami signed him in August after the Cardinals cut him.
Nkemdiche tore an anterior cruciate ligament last season.
The Cardinals made Nkemdiche the 29th overall choice in 2016. He has played 29 games with six starts in his career, making 44 tackles, 4.5 sacks and two forced fumbles.