The England prop was handed the punishment for a dangerous tackle on Leeds centre Alex Sutcliffe during Friday’s Super League win over the Rhinos by the Rugby Football League’s match review panel.
Saints launched an appeal and an independent tribunal downgraded the offence from Grade C to B after agreeing the tackle was careless rather than reckless.
Walmsley will still miss Friday’s derby with Wigan but will be free for St Helens’ trip to Catalans Dragons on Thursday week. He has also been fined £500.
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