Why Arsenal should have been awarded a penalty against Hull despite Kai Havertz being offside

Arsenal were denied a penalty against Hull City on Saturday after VAR ruled Kai Havertz offside before he was hauled down by Nobel Mendy. Home fans briefly celebrated when referee Farai Hallam first announced the foul, but Hull were instead awarded a free kick, leaving Mikel Arteta fuming on the touchline during a tense first half at the Emirates Stadium.