The winger admitted a charge of grade D punching after being referred to a disciplinary hearing by the RFL’s match review panel.
Clare was sin-binned in Tigers' pre-season win at York City Knights, along with opponent Liam Harris.
He pleaded guilty to a similar offence and was also suspended for three games, ruling him out of Monday's Betfred Championship opener against Featherstone Rovers.
Clare was fined £500 and Harris - as a lower division player - £300.
York's Jacob Ogden will also be unavailable for York's home clash with Rovers after accepting a one-match penalty notice for grade B dangerous contact against Tigers.
But teammate Pauli Pauli, a former Wakefield Trinity forward, could make his competitive debut for Knights after Tuesday evening's tribunal found him not guilty of grade B dangerous contact in the loss to Tigers.
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