Brett Ferres has been banned for Leeds Rhinos' next six matches after his tackle left Wigan Warriors centre Oliver Gildart with a back injury.
The Rugby Football League announced on Tuesday that Ferres has been found guilty of Grade E 'dangerous contact' and will serve a six-game suspension.
The England international pleaded guilty to 'dangerous contact' but challenged the grading, which a tribunal kept at Grade E.
Ferres was sent to the sin bin following the tackle on Gildart in last Friday's Super League meeting at Headingley.
Warriors coach Shaun Wane has confirmed Gildart will spend up to three months on the sidelines.