The incident happened late in the second quarter, as Ruggles was standing on the mark for Isaac Smith.
Smith played on and took on Ruggles, who was greeted with a strong bump from Gibson.
Ruggles took his time in regaining his feet, and was helped from the field by the Cats’ trainers and immediately taken into the club rooms.
Following the half time interval, Ruggles was ruled out for the remainder of the match.
— AFL (@AFL) April 17, 2017