There are four pools and five nations in each. But beyond the 20 countries competing at the Rugby World Cup is another critical selection — that of the match officials (MOs) or Team 21, as they’ve become known.This consists of 12 referees, seven assistant referees (ARs) and four Television Match Officials (TMOs).The management of the team is led by World Rugby Referee manager Alain Rolland from Ireland, with his fellow selectors Joel Jutge (EPCR Referee manager), Lyndon Bray (SANZAR Referee manager), Nick Mallett (ex-South African Coach). Anthony Buchanan from Wales as the chairman of the selection group. Allied to this in analysing the MO’s performance are Paddy O’Brien (WR 7s Referee manager), Craig Joubert (WR 7s Referee coach) and Wayne Erickson (former Australian international referee).Further support is given by WR game analyst Rhys Jones, with Matt Blair looking after all the fitness aspects, and Tracy O’Callaghan from Ireland handling all the administration.How was this team of match officials selected? Since RWC 2015, more especially over the last couple of years, there has been constant appraisal of the performance of all those selected, and of course, of those who were also in the frame but ultimately didn’t make the cut.There is…