A "reckless challenge" refers to when someone takes a dangerous and careless action, usually in a competitive or confrontational situation, without fully considering the potential consequences or risks involved. Full definition
In that game he could have been given two red cards for reckless challenges. (justarsenal.com)
One guy says reckless challenge, another guy says violent conduct. (sbnation.com)
Offences in the 1992/93 season comprised an elbow in the face of Newcastle's Franz Carr, a run - in with Steve Bull of Wolves and a pair of reckless challenges on Ted McMinn of Derby. (westhamway.net)