▁players ▁ch asing ▁the ▁ball ▁into ▁the ▁opposition ' s ▁territory , ▁and ▁the ▁other ▁side ▁trying ▁to ▁retrieve ▁the ▁ball ▁and ▁advance ▁it . ▁The ▁drop k ick ▁must ▁make ▁contact ▁with ▁the ▁ground ▁before ▁k icked . ▁If ▁the ▁ball ▁does ▁not ▁reach ▁the ▁oppon ent ' s ▁ ▁line ▁ 1 0 ▁meters ▁away , ▁the ▁oppos ing ▁team ▁has ▁two ▁choices : ▁to ▁have ▁the ▁ball ▁k icked ▁off ▁again , ▁or ▁to ▁have ▁a ▁sc rum ▁at ▁the ▁centre ▁of ▁the ▁half - way ▁line . ▁If ▁the ▁player ▁with ▁the ▁ball ▁is ▁tack led , ▁frequently ▁a ▁r uck ▁will ▁result . ▁ ▁Games ▁are ▁divided ▁into ▁ 4 0 - min ute ▁hal ves , ▁with ▁a ▁break ▁in ▁the ▁middle . ▁The ▁sides ▁exchange ▁ends ▁of ▁the ▁field ▁after ▁the ▁half - time ▁break . ▁Sto pp ages ▁for ▁injury ▁or ▁to ▁allow ▁the ▁ref eree ▁to ▁take ▁discipl inary ▁action ▁do ▁not ▁count ▁as ▁part ▁of ▁the ▁playing ▁time , ▁so ▁that ▁the ▁el apsed ▁time ▁is ▁usually ▁longer ▁than ▁ 8 0 ▁minutes . ▁The ▁ref eree ▁is ▁responsible ▁for ▁keeping ▁time , ▁even ▁when — as ▁in ▁many ▁professional ▁tournament s — he ▁is ▁assist ed ▁by ▁an ▁official ▁time - keeper . ▁If ▁time ▁exp ires ▁while ▁the ▁ball ▁is ▁in ▁play , ▁the ▁game ▁continues ▁until ▁the ▁ball ▁is ▁" de ad ", ▁and ▁only ▁then ▁will ▁the ▁ref eree ▁blow ▁the ▁wh ist le ▁to ▁signal ▁half - time