The Ulster number eight was handed an eight-week ban after he was found guilty of striking Cardiff Blues back Rhys Patchell on the head with his forearm during their match last weekend.
The disciplinary committee…found that the incident was at the top end of the World Rugby sanctions for this type of offence, meriting a 16 week starting point.
Independent PRO12 disciplinary committee statement
The action resulted in Patchell, 21, leaving the field on a stretcher and spending a night in a Belfast hospital before returning to Cardiff a day later, where he is now under the care of the Blues medical team.
Kiwi Williams was sin-binned at the time, but was cited and found guilty of misconduct contrary to Law 10.4 (a) at an independent PRO disciplinary hearing, chaired by Roger Morris (Wales) along with Rhian Williams (Wales) and John Doubleday (England).
But mitigating factors saw a potential 16-week ban halved, meaning the player can return on 1 September in time for the start of the 2015/16 season, ruling him out of the PRO12 play-offs, should Ulster maintain their current second place in the table, as well as their pre-season friendlies in August.
“In the absence of any aggravating factors and in light of several mitigating factors, including the player’s exemplary previous playing record, the disciplinary committee applied an eight-week reduction from the entry point and suspended the player from playing for eight weeks,” a PRO12 statement read.
While Ulster know when their player will be next available for them, the Blues are in a position of not knowing when outside-half/full-back Patchell will return.
The youngster will have to go through graduated return-to-play protocols before being considered ready to return to action, ruling him out of the Blues’ trip to Rodney Parade to take on rivals Newport Gwent Dragons in the European Challenge Cup quarter-finals.
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